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Found 44 results

  1. The 2005 Corolla has and AIR FUEL RATIO SENSOR not the convention oxygen sensor. What is the difference between a AIR FUEL RATIO SENSOR and CONVENTIONAL OXYGEN SENSOR. How many air fuel ratio sensors are on the 05 Corolla. Does the 07 Camry have an AIR FUEL RATIO SENSOR. When do you change one of these out or only if they fail. Thanks.
  2. Mileage is about 150K. As far as maintenance I've only had a few oil / oil filer changes, and I've replaced the air filter, most recently last month. I bought some NGK Iridium IX plugs after seeing the look on my friends face when he realized I hadn't even checked the plugs in the 9 years that I've owned the car. I've also cleaned the MAF sensor, once last year and again last month. Other than that I just check to make sure I have enough oil. Here's a pic of the old plugs: http://imgur.com/dZjIk20 I'm not sure if I have oil consumption, just know for certain that I have a leak. Mileage has varied between 20 and 24 mpg for as long as I've owned it, not sure if that's good, bad or average. I haven't noticed any smoke on startup, or anytime really. I do have what looks like soot built up on the bumper above the exhaust, but I don't know if that's just because I haven't washed it in a long time or what. The battery is about a month old, my old one needed to be replaced after almost 4 years. It starts just fine, even after it stalls. However, after driving a lot, particularly after driving on the freeway is when it stalls the most. If I stop somewhere, like at a store, the car often won't start unless I let it sit there for anywhere from 2-15 minutes. However, if it stalls and I immediate try to start it it will start just fine. It's like letting it sit off for a few minutes makes it not want to start until it's had a chance to cool or something. Today a nearby tow truck operator offered to get it started for me by spraying ether into the air intake. I hesitantly agreed, and he sprayed Hot Shot Starter Fluid into the hole in the airbox cover, closed it and had me start it, and it worked. If I do have a vacuum leak, and that makes the air/fuel mixture lean, does spraying that fluid into the air intake then help to correct the air/fuel ratio? Or does the fact that it worked mean that a vacuum leak isn't the problem? Is there a good tutorial on cleaning the TB for my engine? Thank you for your help
  3. That's right. 2005+ with DBW have an upstream (primary) wideband airf/fuel ratio sensor. It's certainly tired and weak if still the original. Denso # 2349052 http://www.rockauto.com/catalog/x,carcode,1432846,parttype,5132 http://www.ebay.com/itm/Air-Fuel-Ratio-Sensor-OE-Style-Left-DENSO-234-9052-/370843535837?pt=Motors_Car_Truck_Parts_Accessories&hash=item5657ff49dd&vxp=mtr
  4. Bad fuel injectors usually cause misfires, engine stumbling, rough idle, poor engine power, and reduced fuel economy. Problem is - lots of other tings can cause the exact same symptoms. Cleaning the fuel injectors would be my first though. In tank products, additives that you add to the gas tank to clean the injectors during operation helps some owners. Best to pick fuel system cleaners that have lots of PEA additive in it (made by Chevron) - Chevron Fuel system cleaner, Gumout with Regane, Vavloline Sympower, and my choice - Redline SI-1 Complet Fuel System Cleaner - all have some amounts of PEA in them, with Redline having the most. If that cleaning doesn't work - you'll have to clean them with a pressurized fuel rail manifold - they basically connect cans of concentrated cleaner directly to the fuel rail - disconnect the fuel line and run your car from the special cleaner fuel. Replacing them would be a last resort sort of thing - if you have diagnosed a bad injector (draws too much power, draws no power, intermittent in operating, etc.) - then you'll have to replace it. Pretty simple in these cars, assuming you have the SST or special service tools to disconnect and relieve fuel pressure from the injector rail before you try and remove them. I'd look into more likely possibilities of bad gas, dirty throttle body, bad air fuel ratio sensor, vacuum leaks, worn plugs, etc. - then suspect injectors. You'll definitely have to do some more diagnosing to eliminate possible culprits and there are a lot of them that can lead to these particular symptoms.
  5. As dom mentioned, the wideband or AFR (air fuel or air fuel ratio sensors) are only on the 2005+ Corollas. The 8th gen - 1998-2002, all use conventional O2 sensors. Problem might be with the terminology - some mechanics incorrectly use terms to describe a part or diagnosis. P0171 can sometimes come from an exhaust leak - you could be bleeding exhaust or siphoning fresh air before the upstream (#1) sensor before it can read it - make it read lean. The downstream O2 sensor (#2) sensor is mainly used for catalytic converter efficiency checks, doesn't really play too much with the air/fuel feedback loop. Other things to check that could cause a P0171 - clogged or faulty injectors, stuck open PCV, excessive knocking, any number of vacuum leaks as mentioned by dom. Being intermittent also makes it a lot harder to diagnose. Have to catch it when it is happening to see if you can effect a fix.
  6. Your car has no Air/Fuel (wideband) sensor. It has oxygen sensors. One on intake manifold for air/fuel ratio feedback to ECU in closed loop operation, and one downstearm of catalytic converter(s) to monitoe catalytic efficiency. To address P0171 lean air/fuel mixture code, you need to find the cause and rectify. It is usually from a vacuum leak on intake, somewhere between throttle body valve/idle air control valve and intake manifold gasket including PCV and vacuum hoses.
  7. Two things: I had the front struts replaced on my 06 CE last week since the car was in the shop for body work (hit a deer). Well, they did a front end alignment, and was well. Then I put my snow tires (new Blizzak WS-60's) on for the winter, and it feels like the rear end alignment is off now. The car feels like it is pushing down the road a little rather then going perfectly straight. Can the rear end on these cars even be aligned, considering they have a solid rear axle??? The other issue at hand is that I had the air/fuel ratio sensor replaced at the same time. I had a CEL on that was showing bank 1 lean, the shop ran the MAF tests, and determined the issue to be the AF sensor. Well, this morning the CEL came back on. I'm going to clean the MAF tonight to see if that makes a difference, but if not, anyone have any ideas? The car has 140k miles on it. Thanks! ~Chris
  8. intakes in general are not a good idea for low displacement engines. the 1zz-fe runs lean comparably to other vehicles as it is. an intake will probably increase air to fuel ratio (not sure). this might give you less power overall but increase throttle response. Fuel economy might also benefit. But the loss of power is unacceptable. k&n oil also messes with your MAF sensor, i had to clean mine with isopropyl for a while until it stopped rough idling.
  9. Howdy, I thought I'd share what I found works on upgrading/changing out instrument gauges etc. If you're stuck with a corolla or prizm with just a speedometer, don't loose hope... Even some models with all power options seem to be lacking the tach which was the case with mine. I think the following holds true for 98-02 models, but it looks like later model instrument panels in 9th gen rollas or prizms may still be the same as the 8th gen, but someone would need to confirm that to be sure. In some reading on various blogs/forums, it sounded like some were swapping out instrument clusters successfully, so I thought I'd try. I found a 99 corolla that had an instrument cluster with the tach and removed my speedometer from my old cluster and installed it into the cluster I got from the 99 corolla and everything turned out to be an exact swap and connectors on the back of the instrument panels were the same. Just be gentle when removing the hardware that holds the speedometer onto the cluster housing as you don't want to damage the flex circuit. Oh, you do have to take apart the cluster housing to get to get to your original speedometer, so do go easy with that too, as the plastic tabs etc. aren't very sturdy. I found that it was good to check all bulbs to make sure ones that were burned out or dark, were replaced with good bulbs. All the different indicators seem to all work and function normally even though they were in different locations on the old cluster. The tach works fine, and the only thing amiss, was the digital display under the tach showed something like an '-E' which after much research, found out that the display was for the outside temperature display, and without the outside sensor which the manuf doesn't bother to plug into the wire harrnes, get's an error reading. It turns out that there's a connector with nothing attached in front of the radiator and behind the grill where a short plastic sensor about 1 1/2" long plugs into that connector which then sends temperature readings to the instrument cluster. Once I found that out, I went to a junk yard and found a prizm/corolla with a tach and sure enough, there was the sensor plugged in. Got the sensor and plugged it into my car, and now I have outside temperature being listed on the replacement instrument cluster. All is now working and complete with the upgraded cluster. Why they would make/sell an LSI Prizm with all power and skimp on not putting a cluster with a tach is beyond logic... I think I spent about $15 for the instrument cluster with the tach, and a few bucks for the sensor. Having a tach makes working on an engine much easier as well as being able to get a feel for what rpms are giving you the best fuel economy etc. Adding a scanguage that plugs into the OBDII connector just under the dash on the left, that fits nicely in the little vanity drawer in the dash on the left by the driver door without having to hard mount it or velcro it somewhere ON the dash works great if your vehicle trim has it, and gives all kinds of additional real-time data about what's going on in the engine, shift points and rpm levels, and how that affects fuel economy. I originally was hoping there would be a nice fit putting the scanguage inside or along side of the instrument cluster, but no such luck. Having it to the left and kind of down and slightly behind the steering wheel makes a person have to lean over to see some of the readings, but if your car has the little vanity drawer that opens up, it's an almost exact fit and you can route the cable through the opening and then into the OBDII connector so that there are no cables hanging down which is nice. The only thing at least the scanguage or maybe the OBDII system is lacking, is reporting the air/fuel ratio. The ECU has to be keeping track of that in some manner, so it sure would be nice if the OBDII system would also report that. I did find an external air/fuel ratio guage that I think hooks up to the before cat O2 sensor, but that's just one more thing I will have to hang inside on the dash. A scanguage does show open or closed loop status, and was helpful in finding out that the pre-cat O2 sensor was bad as a result of the prior owner sentencing an amost new engine to death by not bothering to change the oil regularly, causing sludge buildup, stuck oil rings and buring oil and the final blow, having an exhaust cam sprocket sheer off due to the cam seizing due to lack of oil). After 1/2 year of searching to find if anyone else had successfully dealt with the 1ZZFE oil consumption problem, I struck out on my own and if I can figure out how to upload pics, will post some pics and notes as to what I did to modify the pistons to avert that problem. Only in the last couple days did I notice someone else posting a very good detailed overview of an engine teardown and piston modification routine, but I think my piston mod is a bit more classy Due to the PO not changing the oil, it turned out it damaged the pre cat sensor (am hoping he didn't deep six the cat and aft O2), but it wasn't until I put the scanguage on that it was evident the pre cat O2 was bad even though no engine codes were being reported as the O2 sensor was very slow to cycle etc. Modifying the wire harness and putting a scope on it confirmed it was bad, so people need to make sure you change your oil before the oil looses it's protective properties. From what I've read, the pre-cat O2 sensor is supposed to have about a 1 second cycle back n forth on it's waveform, and open/closed loop status of the ECM should change very quickly i.e. in the milliseconds, not take seconds to switch from open to closed loop which this one was doing. The next step, now that I have a tach and realtime monitoring, is to look into adding hydrogen... I may have made a mistake on planning to do the hydrogen on a post 1995 vehicle (wanted the OBDII data), as the pre OBDII cars had less computer controls and are supposed to be easier to fool/program the ECU when modifying the air/fuel mixture, and of course going back to non ECU cars with carbs and no ECU would probably be much easier. Was hoping to do some serious volume with hydrogen systems, but not sure I can be successful in over-riding the ECU and the air/fuel mix to where substantial mileage gains are able to be realized by trying to add substantial hydrogen volume. Hope this feedback on upgrading the instrument cluster helps others out. It's a drag to try to figure out what an engine is doing if you don't have a tach in front of you and was a lot easier and cleaner looking than having to hard wire in an after market tach and either hard mount to the hood or cut and hack on the dash to mount one on the older cars. Also, if anyone has had any experience on adding hydrogen on these 8th gen engines, do let me know. Thanks!
  10. Howdy, just thought I'd throw in a couple cents. If it doesn't reduce your vacuum flow, using a fuel filter would be a start, but as soon as the oil gets into that filter, it could begin to restrict the pull from the PVC valve and like mentioned, start to cause idle problems. If you want to stop the junk but let the gasses through, might consider using a compressor air filter. They are designed to handle pressures and oils and have a nipple at the bottom of the glass or clear plastic bowl to drain out condensation/collected liquids. Regular filters are kind of big (about 2-3 in dia and 4-6 in in length, but at least in the recent past, Harbor Freight had a cute little one that's about the size of that fuel filter you're showing. Most air line condensation filters don't incorporate additional fiber filter inserts, but just have a disc near the top to block liquid spatter and to keep the liquid in the bowl. A perfect design I think for your DIY oil catch can, eh? Just make sure you put it inline in the normal direction of air flow so the disk inside is blocking any splatter (They usually have an arrow on the body showing which way the air should flow through. Another issue you need to consider. Most of the oil consumption is probably due to collapsed oil rings. Notorious problem in these engines and although not as serious in older engines, cars with catalytic converters will tend to plug up if too much oil is being burned. 15w40 is pretty thick oil even in hot climates. If you're stuck using a thicker oil to DIY fix the oil consumption problem, I'd advise getting a brass tee at the hardware store and carefully installing an oil gauge and mounting it inside the engine compartment to monitor oil pressure. I blend my oils due to custom designing when rebuilding, to make sure my pressure is not to low or too high. Oil pumps have a bleed-off valve that kicks in at about 80psi. If when the engine has been running and warm and at say 2,000rpms oil pres is above 75psi at the weather temperature climate you are driving in, your oil is probably too thick. You don't want the oil pressure to be much lower than about 5-6psi when idling after the engine gets good and hot, but you might want to try 10w40 after putting an oil guage on the engine and see if you can get a good compromise on oil consumption vs. oil pressure. 5w30 is standard grade, but as you mentioned you are experiencing 1.5 qts per change, but at what duration? If you're going 4-6 thou per change, I don't think that would be so bad to warrant risking oil starvation at cold starts or in cold climates. If you're consuming 1qt per 1000 miles as many have commented have happened, you might be able to reduce what actually goes down the TB with your oil trap, and keep some of it from being 'burned off'. If it gets below 1000 miles per qt, then you probably have seriously stuck/collapsed oil rings. some have had some success in reducing oil consumption by doing the sea foam thing, but my guess is that the oil rings were getting stuck but not yet collapsed due to excessive heat that is caused when there is no oil flowing around those oil rings to keep them from getting too hot. If you get down to a qt of oil every 500 miles, you may soon be facing catalytic converter and/or the before 02 sensor failure and need to probably consider doing at least a ring job overhaul. So far on the 1ZZFE with my piston mods, have put on about 4kmiles after the initial 500mile oil change and now due an oil change, and have not consumed a drop of oil, but then I don't hot dog much these days like I used to when trying to out-run my guardian angels. Because I did some mods to my engines (and because a jerk machinist machined the engine not as a consumer engine but as if it was going to be run on the track, i.e. looser clearances than spec, I blend my oils. I mix a ratio or 5w30 and 10w40 so that when engine is cold, the oil pressure at 2,000 is at or a bit below 80psi but when hot, the oil pressure at 2,000 rpms is at least 40 and at least 5 or 6psi at idle. I once had a offroad racer long ago that I had straight weight in... All was good until I went to go visit a girlfriend and when I left late at night it was at or just below 0o out. I climbed in and started up and roared off, only to have main bearings seize up and lock up the engine. Very embarrassing to have to drag your car home in front of the purty girl... At all temps, don't want the oil too thick, or two thin. One 1ZZFE engine in a car I bought from a dealer and was driving home late at night froze an exhaust cam due to oil starvation and spun the sprocket off of the exhaust cam. Cause? The idiot that owned it before had not changed oil regularly and the engine although spotless on the outside was the worst gummed up engine I've ever torn down. Looked to be a recently rebuilt engine too. Lesson? If you can't see the cams through the oil fill cap, pull a valve cover before buying a 1ZZFE car to make sure the engine isn't sludged and gummed up, which will usually be death to one of these engines, as well as long before destroying the oil rings on the pistons. These cars from what I read can burn as much as 1 qt every 500 miles and not puff a whiff of smoke out the back end (I guess the cat does a pretty good job of eating that oil, at least until it dies from all the oil burn-off). Just a few cents worth. Cheers
  11. Glad to hear the problem was solved, could have been a real PITA without accurate diagnosis. However, this is not a mistake with the code itself. The bad gas mileage is always in some way related to the mass airflow sensor. The code that engine threw (P0171) points to incorrect ratio of fuel/air due most likely to a dirty MAF sensor. In this case it was due to vacuum leak. Only Toyota knew about the gasket problem. Stuff like this can drive you crazy. You could have replaced the MAF sensor and experienced no improvement.
  12. Did they provide the actual OBD-II codes by chance? Did they run a real-time out or capture any frame data when the car was running? This car uses an air fuel ratio sensor instead of an O2 sensor - sort of like a high resolution/high performance O2 sensor. The MAF malfunction and faulty O2 sensor can cause much of the issues you are seeing, though for a 2009 model year, unless the engine was modded or otherwise played with or has an enormous amount of mileage on it - they should not have died this soon. Misfiring could be a symptom of the other two malfunctions. These also point to a possible ECM malfunction - though hard to say without some realtime data captured during operation or even a snapshot of an operational frame. As for other possible culprits - there are number of them, from an ignition timing error, problem with the chassis grounds, faulty fuel delivery system or consistently bad tanks of gas, clogged or fouled injectors, etc. ntermittent behavior like this is hard to diagnose, especially by a shop that doesn't have experience with this particular engine - Toyota dealers are usually your best shot, unless that particular shop is incompetent. If it was only the misfire, or MAF, or AFR sensor alone - that would make it easier to diagnose over the web - but all three makes it much more difficult, as they point to a number of possible culprits. Definitely a time to take it to a competent shop. Car should still be under warranty - unless you ran over the 5yr/60K mile powertrain mileage portion. That case, it could be argued that the MAF and AFR sensor are essential for emissions requirements - as those are covered under the 8yr/80K mile warranty period. Definitely need to get this to a dealership to start a papertrail on it. I
  13. Try this site: http://www.troublecodes.net/Toyota/ [Directions are just cut from the site and listed below] Basically jumpering two pins to enable diagnostic mode - TE1 and E1. Toyota makes a special tool to short the pins (looks like a key) or you could just use a paperclip or some solid core jumper wire. Or you could pickup an OBD-I reader for around $30-$40. - Turn ignition switch to ON position. - Do not start the engine. - Place a jumper wire across TEl and El terminals in engine check connector. - Count number of flashes from CHECK ENGINE light. NOTE: If system is operating normally (with no detected faults), the CHECK ENGINE light will blink continuously and evenly about 2 times a second. Otherwise, the light will blink a number of times equal to the trouble code as follows: - The light blinks only (.5 second ON, .5 second OFF) when indicating a number. - The light will be OFF for 1.5 seconds between the first digit and the second digit of the code. - If more than one code is stored, the light will be OFF for 2.5 seconds before the next code is displayed. - Once all code(s) have been displayed, the light will be OFF for 4.5 seconds and then the whole sequence will repeat. - The diagnostic code series will continue to repeat as long as the check connecter terminals TEl and El are connected. When finished, remove the jumper wire. Clear the codes from the ECU memory (remove negative battery terminal for a minute or so). Limited number of codes - so it can be a blessing or curse, depending on what is wrong. OBD1 Codes 1 Normal Condition 2 Air Flow Meter signal 3 Ignition signal 4 Engine Coolant Temperature Sensor signal 5 Oxygen Sensor 6 RPM signal (Crank Angle Pulse) 7 Throttle Position Sensor signal 8 Intake Air Temperature Sensor signal 9 Vehicle Speed Sensor signal 10 Starter signal 11 Switch signal 11 ECU/ECM 12 Knock Control Sensor signal 12 RPM signal 13 Knock Control CPU (ECM) 13 RPM signal 14 Turbocharger Pressure 14 Ignition signal 21 Oxygen Sensor 22 Engine Coolant Temperature Sensor signal 23 Intake Air Temperature Sensor signal 24 Intake Air Temperature Sensor signal 25 Air-Fuel Ratio Lean 26 Air-Fuel Ratio Rich 27 Sub Oxygen Sensor signal 28 No. 2 Oxygen Sensor signal 31 Air Flow Meter signal (Vacuum Sensor signal) 32 Air Flow Meter signal 34 Turbocharger Pressure signal 35 Turbocharger Pressure Sensor signal 35 HAC Sensor signal 41 Throttle Position Sensor signal 42 Vehicle Speed Sensor signal 43 Starter signal 51 Switch signal 52 Knock Sensor signal 53 Knock Sensor signal 54 Inter-cooler ECM signal 71 EGR System 72 Fuel Cut Solenoid signal 78 Fuel Pump Control signal 81 TCM Communication 83 TCM Communication 84 TCM Communication 85 TCM Communication
  14. My understanding was that DBW was implemented more for traction control than performance, though it does have a larger inner diameter than the standard cable throttle body and the ECM is reprogrammed to maximize fuel efficiency. The ECM will cut the throttle when it sees wheelspin - gets annoying at times, plus the lag doesn't help matters. There are times where you can "feel" the car fighting you, ie. when coasting, the throttle is still open to help with pumping losses, but give the impression that the car does not want to slow down. The AFR sensor though has a much higher sensitivity and wider sensing range than the traditional O2 sensor, so that would have a marked influence on fuel economy. The conventional O2 sensor only senses very close to the stoichiometric ratio, anything above is lean, anything below is rich. The AFR sensor acts like a wideband O2 sensor, able to measure extremely lean and rich conditions, as well as stoichiometric. This ability to read very lean helps the ECM run optimal air/fuel/timing maps for conditions where you have low loads and can run a leaner than normal mix. As for the end result - having better performance and/or economy from these changes - seems to be a mixed bag. Some saw better performance/economy, others did not. What was sure, was the amount of additional headaches that were added to the operation/maintenance of the vehicle from these additions. You can run a cable throttlebody in place of the DBW setup - as many have done this when they swapped out a dying 8th gen 1ZZ-FE for the newer 1ZZ-FE setup. Car still will operate, but the ECM will likely run in a degraded more, as it cannot see the DBW unit. Not really an issue, as most ECMs have multiple failsafes for sensors that "disappear" - I personally would not shy away from a 2005+ engine if it was the right price.
  15. Results for first post-Gumout treated tank of gas: Odometer: 103,563 km Distance since last fill: 389 km Liters used: 33.1L Mileage: 8.5L per 100 km (27.7 mpg) This is a drop from both my previous fill and my typical 30 mpg before Gumout, although there are a couple likely causes it for it: 1. Much more city and less highway then both the Gumout run and my usual driving habits. My tires are getting so worn that I`ve been avoiding the highway as much as possible. Typical ratio is about an even split, and on the Gumout run it was 70-80% highway. This run was closer to 20% highway, if that. 2. Low tire pressure. I`ve been neglecting to fill my leaking rear passenger tire (needs to be replaced soon) as often as I used to, and in having to fill it more and more frequently, I`ve also been neglecting the rest. I typically over-inflate to 40 psi. Only one tire`s been holding that. The worst on the other three I`ve seen on this fill were 32 psi, 21 psi, and 18 psi. The lowest numbers are on my rear tires that I`m planning to replace asap. 3. Smaller `sample` mileage. I replaced my PCV valve today and then hit the gas pump next door and filled where I usually do (quarter mark on the fuel guage). Previous fill it was below the empty mark and I waited for the gas light to flash on before fillingh. The factory PCV valve was badly gummed. Actually, that`s an understatement. It was down right filthy. Best $10 I ever spent. Between the Gumout, replacing the air filter, cleaning the MAF O2 sensor and throttle body and butterfly valve, and now replacing the PCV, the work and small associated costs (this has all been easy DIY stuff) are beginning to pay big dividends. I`ll find out tomorrow morning when I get off work after my 12 hour shift if the PCV was also the culprit behind the cold start issue I`ve been having (though it needed to replaced either way). If it has, I can scratch another item off the to do list; if not I`ll eventually have to figure out a way to get the stripped phillips screws off that are in the way of the IAC valve. -Spyder
  16. False. A dirty air filter will NOT harm the fuel economy on a modern fuel injected vehicle with a closed loop feedback signal from an O2 sensor. The O2 sensor assures the vehicle is running at the correct stoichiometric air fuel ratio (14.7). Just because your filter is dirty doesn't mean your engine is getting less air or more fuel. The air/fuel ratio is the same. All that happens when your filter is dirty is the filter has a larger pressure drop across it, so in response, the throttle body butterfly valve opens a little further creating the EXACT same power at the EXACT same air/fuel ratio. Now, fuel throttle, peak horsepower is a different story, where a dirty filter will reduce power. http://blogs.wsj.com/drivers-seat/2010/06/17/top-ten-fuel-economy-myths/ http://www.fueleconomy.gov/feg/topten.jsp
  17. Depends on what you are swapping - just the short block or whole engine. If the former - no worries, the bottom ends are the same between the two variants. If you want to swap in the whole engine - little bit different story. Most of the wiring will have to come out of the Vibe, as well as the sensors. Pedal will have to be swapped as well - as I'm pretty sure that this model year of Vibe has DBW instead of the cable throttle body. You also have to move over the sensors, especially the O2 sensor - as with this engine, it is now a air fuel ratio sensor - has a much wider resolution, that a conventional O2 sensor can output. Intake will have to change - MAF vs MAP issue. Note that the transaxle is geared differently as well - to match the different powerband on the newer engine - the switched from a tubular aluminum intake runner to a shorter composite intake, different ECM air/fuel map and timing, and revised camshaft profile to boost mid-range and upper range power. Concequently, the engine likes to run higher RPMs compared to the 8th generation. Some have retained their old transaxle and swapped it with the new engine - and reported good results, but I'm pretty wary of a big design change. Normally, if the manufacturer changes the gearing that much - it is for good reason. EVAP system is completely changed as well - depending on where you live at - you might have to yank all the EVAP stuff off the donor car to make it "street legal". Not sure if it will happen on your car, but sometimes you'll have to swap the gauge cluster as well. Some cars won't run without the correct cluster. Mazda is that way for example. Since you have both cars there - you have a much better chance to swap the engine drivelines. This kind of swap is doable and has been done before, but it is not for the faint of heart. Wiring is the tough part here.
  18. Disconnecting the battery would be a start - negative battery terminal off for a minute - might help to step on the brake or flip on the headlamps to drain any residual charge. Some cars cannot be reset in this manner - have to be reset with an OBD-II scanner. This is more likely in cases where CAN bus is being used - like in your model year Corolla. Keep in mind that anything that depends on power will also be affected - radio presets, some headunits have builtin security, alarm systems, etc. If in doubt - just pickup a CAN compliant OBD-II scanner at an autoparts store. They are really getting inexpensive and just pulling and reseting a single CEL - it will pay for itself (Toyota dealership's typically charge around $85 for a diagnostic fee). The little bulb thing is the IAT sensor (intake air sensor) - the MAF sensor itself is inside the plastic cylinder MAF housing (should be able to make out two "wires" on the inside of the tube). Backprobing the sensor - you should see a rise in voltage as more air flows over those MAF sensor - so as you increase the throttle - the voltage will increase from the MAF. Same with the O2 sensors, you should be able to see the voltage trace (o-scope is best here) and view the waveform in real-time. Yours will be a little different than conventional O2 sensors, as the 2005+ Corolla models now use an air/fuel ratio sensor instead of an O2 sensor. The sensor is much more sensitive and has a wider sensing band. In other words, the new sensor acts more like a wide-band O2 sensor (read expensive) compared to the garden variety narrow-band O2 sensor. The after cat O2 sensor on the car may flag a code if the heater circuit malfunctions, but generally not considered an issue for a P0171. The only job the rear O2 sensor does is monitor how effectively the catalytic converter is doing its job. The air/fuel mix is determined by the upstream or pre-cat sensor. My suspicion is that once the CEL is reset and the MAF was cleaned carefully - the code should drop away, no more CEL.
  19. P0171 Lean Mixture is more likely a bad exhaust O2 sensor or its eqivalent A/F Ratio sensor in some California emissions cars. If the car hesitates try disconnecting the O2 sensor. If the car no longer hesitates change the O2 sensor. The MAP sensor can cost $300; be sure before you buy one. You might try a salvage yard MAP sesor which will cost a lot less. Ther is also the possibility the fuel pressure is too low. I would measure it before I would invest $300 in a MAP sensor.
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  21. In my 2001 Toyota Corolla, the performance was getting abysmal, and the mileage was extremely poor (28-32mpg highway, low 20s city), even on a straight highway trip. I noticed that on some hills, the engine would rev up a little and then it would downshift out of overdrive, and that it seemed to do it more and more on hills that it used to never have a problem on. As my '95 Previa S/C doesn't do that (and it has a much worse power to weight ratio), it occured to me that the knock sensor was just too sensitive and the timing was getting retarded more than it should have been. What seems to have confirmed it is that when I run 89 octane fuel (rather than the 87 the manual calls for) the performance is much better, and the mileage jumped from about 31mpg highway to over 36mpg (very nearly the original mpg I used to get). So, either the engine is way carboned-up, or the knock sensor is just too sensitive. Does anyone have any ideas on this?
  22. The P0136 code refers to the upstream O2 sensor, or pre-cat O2 sensor. Doesn't necessarily mean a bad O2 sensor - just that the ECM detected a lower than expected voltage from the sensor over a specified period. Possible causes are a short in the wiring, bad chassis ground, if the O2 sensor was recently replaced - could be an impedance mismatch (very common when using a non-OEM universal or aftermarket sensor). If this is the original O2 sensor and you've noticed either a steady decline in fuel economy (lazy or dying sensor) or a sudden drop in fuel economy (dead/dying sensor) - might be time to replace it. The P0171 is probably related to the P0136 - as when the engine runs lean, there will be a higher oxygen ratio presence and the sensor will report a lower voltage. dorman68 makes a good point of trying to clean the MAF sensor first (in the airbox). Not usually a maintenance part, but many have been able to get good results with careful cleaning. After cleaning the sensor - reset the ECM and see if the codes come back. If they don't come back - probably was a dirty MAF sensor. If it comes right back - then check the wiring/connection to the O2 sensor before you replace it. Could be as simple as a corroded connection under the passenger side carpet, right next to the console.
  23. Hi there! I have a Toyota corolla 2001 with 82,000 miles on it. I consider myself very conscious about the mileage I get. Here is my story. I was getting 29-31 mi/gallon mixed highway and city driving and I was kind of concerned. Then, I changed my original Denso spark plugs (iridium) with Bosch (Platinum) and my fuel economy went down to 23 mi/g. I heard from my friend that if you change the spark plugs then you need to reset the computer so that it can readjust the air-fuel ratio as per the plug design conditions. I didn’t like the new plugs so, I cleaned the old plugs as they were looking ok and I got my mileage back to 29-30 (I had also reset the computer this time). I wasn’t still happy with the mileage so I researched and cleaned MAF sensor with Electronic Part Cleaner. I drove about 400 miles without any problems. Then, on next gas filling about 60-70% of my driving was in the city (about 170), and after a trip of about 100 miles on freeway check engine light came on. I didn’t check the code and disconnected the battery to get rid of engine lights. I drove like 500 miles without any problems (city as well as freeway) and then check engine light came on freeway driving. This time I checked the error codes with a scanner and it shows the following conditions: Code P0420 : Catalyst system efficiency below threshold (Bank #1) Speed 60 mi/hr RPM 2906 Engine Load 30.6% Temperature 189 (F I guess) Fuel Pressure -5.5 -3.1 psi Note: I have been using different fuel system cleaners in the past 2-3 months. I guess, I had used about 2-3 12Oz cleaners in this period. When I checked the code, that time I had used fuel economy improver (Gumout). I researched a lot about this P0420 code and now I am very confused. The direct answer says Cat Converter (CC) may be bad but many people had check engine light come again even after replacing CC and my car is not that old as well. Could it be oxygen sensor? If yes, then which one?? When my friend scanned the code she checked the oxygen sensor and she said its working fine but she asked me to search the code first then we will see (She’s not a professional). What is the time response for an O2 sensor?? I forgot to mention that, I didn’t have any drivability problems except a bit slow acceleration (it could be just my mind as well). Today, I have changed my old spark plugs with new Denso IK-16 and following an internet reading, I drove the car with full A/C, two windows open and fans on at full speed to put extra load on engine. The idea was to heat the CC and get rid of any accumulation of contaminants. I could feel faster acceleration with little gas paddle pressed. I haven’t reset the computer yet hoping that it will turn off by itself if CC and O2 sensors are good. Does it sound reasonable?? What else could be the problem?? I will really appreciate any input in this regard. Thanks a lot, Ajay
  24. Depends on how much crap was shot out the exhaust after the treatment. Kind of hit or miss with cars - some are more sensitive than others with this sort of treatment. Doesn't necessarily mean that the quality has gone down for a particular part - maybe the treatment dislodged larger chunks in the one car than another. Possible that enough "crap" got blown down the exhaust pipe to foul a sensor or two - fould plugs like crazy. Doesn't mean that Seafoam automatically is bad - even large amounts of combustion blowby, oil consumption issues, overly rich mixtures can fould sensors just as easily. Old trick was to pull the sensor out and burn off the contaiminants with a torch - though some have indicated that even a torch can leave behind its own contaminants (type of gas varies - propane leave behind organic compounds and with MAPP gas - leave behind quite a bit of hydrogen). But I have noticed that Seafoamed Camrys seem to have more occurances of CEL than other Toyota makes. Not sure if this is indicative of Camrys in general - or that their owners are more keen on trying treatments like these - can't say for sure. The ECM characteristics are quite different between one generation to the next - the 8th gen did fine with a 16bit ECM, but the 9th gen went with a 32bit setup to enable finer control of parameters and handle more sensors with faster data rates. If you are set on replacing parts - Catalytic converter and various sensors - keep in mind that some models have an air/fuel ratio sensor instead of a garden variety narrow band O2 sensor - the air fuel ratio variants have a much broader sensitivity range - similar to a wide-band O2 sensor. Many of those sensors were introduced around the 1998 or earlier (some came out on Toyotas in 1990) - I believe many 2003+ use them now. That's part of the reason why a $60 universal Bosch or similar O2 sensor throws a CEL on come Toyotas.
  25. Sorry All, my code is not the infamous P0420, but P0171. I am running lean on the air/ fuel ratio mixture on one engine bank (whatever that means). Thanks to my local Auto Zone, the probable causes are 1. If one and two codes set together suspect fuel pressure or MAF sensor, 2. Oxygen sensor defective, 3. Ignition misfire-repair or 4. Fuel injector problem. My mechanic cleaned the MAF and he tried replacing the upstream sensor to no avail.
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