The more I think about, there are more paralels between this and the sulfur issue. The sulfur problem boiled down to the some carrs running richer than they should, effectively reducing SO2 (only modestly stinky) to H2S (one of the most smelly substences on earth, rotteneggs).

Now, since 2004, the US fuel is required to be low-sulfur, so one does not see (I mean smell) the H2S issue anymore. Yet, rich mixture at idle would increase RPM, to the extend that the ECU would have to intervene, cutting the speed down. Under some circumstances that would produce an oscillation pattern.

If my hypothesis is correct, the cars affected by this would also have poorer economy, exaust smelling rich on warmup and negative long term fuel trim on OBD2 scan. My LTFT used to be -10% and I reduced that to -3% after vigorous cleaning of the MAF sensor.

 

I agree that the fact that my car is warming up at 2300 rpms instead of the usual 1800 rpms is costing me extra money during that daily warm up process. But once my car is fully warmed up and idling at the normal 800 rpms, I expect that I am getting the same fuel economy as any other like car that does not have the idle hunting issue.

Do you think that your MAF was the root cause of your overly rich fuel ratio and that is why cleaning it had a positive impact on your LTFT?

During the first few minutes of a cold startup before the O2 sensor has become fully operational, do you believe that the ECU is using the MAF sensor readings to better regulate the short-term fuel trim, and if so would that explain how cleaning your dirty MAF sensor resulted in less smell? Did you see your peak cold idle rpms also drop after cleaning the MAF sensor?

"basterdize" - now that's a nice way to put it

The more I think about, there are more paralels between this and the sulfur issue. The sulfur problem boiled down to the some carrs running richer than they should, effectively reducing SO2 (only modestly stinky) to H2S (one of the most smelly substences on earth, rotteneggs).

Now, since 2004, the US fuel is required to be low-sulfur, so one does not see (I mean smell) the H2S issue anymore. Yet, rich mixture at idle would increase RPM, to the extend that the ECU would have to intervene, cutting the speed down. Under some circumstances that would produce an oscillation pattern.

If my hypothesis is correct, the cars affected by this would also have poorer economy, exaust smelling rich on warmup and negative long term fuel trim on OBD2 scan. My LTFT used to be -10% and I reduced that to -3% after vigorous cleaning of the MAF sensor.

 

I agree that the fact that my car is warming up at 2300 rpms instead of the usual 1800 rpms is costing me extra money during that daily warm up process. But once my car is fully warmed up and idling at the normal 800 rpms, I expect that I am getting the same fuel economy as any other like car that does not have the idle hunting issue.

Do you think that your MAF was the root cause of your overly rich fuel ratio and that is why cleaning it had a positive impact on your LTFT?

During the first few minutes of a cold startup before the O2 sensor has become fully operational, do you believe that the ECU is using the MAF sensor readings to better regulate the short-term fuel trim, and if so would that explain how cleaning your dirty MAF sensor resulted in less smell? Did you see your peak cold idle rpms also drop after cleaning the MAF sensor?

Well, I never paid much attention to the idle, as it was not a problem to me and I live in Gulf region.

Before the O2 sensor kicks in, the ECU calculates fuel needs based on MAF alone, so if MAF is off fuel ratio is off. I did 2 cycles of MAF cleaning in the span of several months. The LTFT is near 0 and MPG is up 10% or so.

I did 2 cycles of MAF cleaning in the span of several months. The LTFT is near 0 and MPG is up 10% or so.

Thanks for your answer.

How did you go about cleaning your MAF sensor and what was the time span between when you bought the car (new?) and when you did the 2 cleanings?

Why was the second cleaning necessary?

From looking at the sensor before cleaning, was it visably dirty in anyway?

I read that these sensors use very delicate platinum wires that should not be touched or contaminated. True?

Since my car did this idle hunting from day one, I assume I had a clean MAF sensor out of the factory, so I don't hold out much hope that my MAF sensor is at the root of my problem, although it would be great for me if that was the case.

I did 2 cycles of MAF cleaning in the span of several months. The LTFT is near 0 and MPG is up 10% or so.

Thanks for your answer.

How did you go about cleaning your MAF sensor and what was the time span between when you bought the car (new?) and when you did the 2 cleanings?

Why was the second cleaning necessary?

From looking at the sensor before cleaning, was it visably dirty in anyway?

I read that these sensors use very delicate platinum wires that should not be touched or contaminated. True?

Since my car did this idle hunting from day one, I assume I had a clean MAF sensor out of the factory, so I don't hold out much hope that my MAF sensor is at the root of my problem, although it would be great for me if that was the case.

I failed to mention that I also had the TSB ECU reflash for sulfur in the meantime too, but did not affect MPG like the MAF cleaning.

Yes, MAF sensor is very delicate but well hidden in the sensor's plastic housing. Use pure acotone or comercial "electronic" cleaner. Could be a long shot but wouldn't hurt. My car had 2.5 years when I tried the cleaning.

We are officially out. We are trading BOTH of our Corollas in for Hondas or something else. We went back to where we originally bought the cars from and it wasnt pretty. I cant believe the way we were treated. The service manager wouldnt even answer any questions face to face regarding the situation. He all but challenged me to a fight on the parking lot. This guy was textbook definition "Corporate Richard Sucker". How is it that Toyota screws up on a design issue and it becomes completely MY fault, responsability and problem? They might as well not come with a warranty at all. Toyota could NOT have handled this whole situation any more poorly then they did. We were lied to from every single level. My wife and I are really in awe. Words cant describe my frustration and disapointment. This could of been handle WAY better. I love how these cowards broke the news to me also, over a conference call-- pansies. They had the "We already got your money, why should we care?" attitude. They didnt even have the ballzies to tell me to my face. My wife is almost heartbroken. Time to start over. There is NO WAY to patch things over. I cant believe they got me for as much money as they did.

Can anyone give me good some sites to help research new vehicles? Any suggestions on what we should get? My wife is looking at Accords.

Sorry to hear about your story. That's really amazing. I would definitely write down the names of everyone involved and the whole story with dates and facts on paper. Keep it very professional and send it to Toyota Corporate customer service. If you don't get a response in 4 weeks. Send a copy to 3 or 4 TV stations and see if they are interested in the story. Whne I lived in Detroit they used to have a segment on stories like this. Occasionally programs like 20/20 will take this type of thing and combine it wiht 2 or 3 other people that have been screwed on a warranty issue. Might be some nice revenge.

What car to get, depends a lot on your price range. I've moved over to the Honda camp, but I still think this forum is interesting and I like Toyotas too.

The great thing about Accords is that they are feel fairly sporty for a midsized sedan, and have smooth motors and nice gearboxes. They have better suspension systems that Toyotas but at the price of less interior and trunk space. I'm very happy with mine. The 4 cylinder is adequate but if you afford spending about $25,000 you can get a V6 with a 6 speed manual in the sedan or coupe. If your on the budget however, a Accord LX with a 4 cylinder and 5 speed manual is a great buy has a better power weight ratio than the Corolla, and is a much better freeway vehicle. But you will find that the Corolla takes big bumps and potholes better, and is more nimble in tight traffic. The Accord also has the best feeling brakes IMO of any car I've driven to date.

I alos test drove a Civic and was very impressed. Just as quiet smooth and stable as my Accord, but a little more buzzy on the freeway. The corolla has a little more midrange power, but the refinement on the Civic is leaps and bounds ahead of the Corolla.

If you buy 2 cars together and tell your story to a Honda dealer, you might find that they cut you a good deal. I've also found Honda Dealer service to be much better.

Other cars to consider:

Acura RSX

Volkswagen Jetta

Nissan Altima

Mazda 6

Ford Fusion

Chevy Malibu

(take a quick test drive to remind yousrself why you buy foreign)

Does Chrysler even have a midsized car anymore? The americna auto industry is such a sad state of affairs. The recent Ford commercial makes me feel like they are begging the audience to buy their cars and invest in their stock out of pity. "please please buy our cars so we don't go bankrupt...we're trying really hard ot make a descent car... look. look we bought Volvo... so now all Fords have Euro design"

Sorry to hear you're trading the Corollas because of the idle issue.

I find it slightly annoying but the good points of the Corolla outweigh the bad.

I was also treated poorly by Southeast Toyota when my 03 had a design defect with the door seals. They acted like real a-holes. Dealer tried to help, but had no support from above.

You can do research at edmunds.com. Intellichoice.com is also good.

Toyota makes good cars but has no clue how to deal with customers. If there is something wrong, it's the customer fault. I've seen this attitude over and over again, started with the oil sludge issue.

The sad part is with the increasing market share by toyota, its going to get worse.

Toyota makes good cars but has no clue how to deal with customers. If there is something wrong, it's the customer fault. I've seen this attitude over and over again, started with the oil sludge issue.The sad part is with the increasing market share by toyota, its going to get worse.

 

Welcome to EVERY car maker. Not just Toyota. Everyone is doing this and Toyota is NOT the worst. We've only had two warranty issues fixed, but they were acually fixed. We are having a lot better with our Toyota then the last car we had.

How is it that Toyota screws up on a design issue and it becomes completely MY fault, responsability and problem? They might as well not come with a warranty at all. Toyota could NOT have handled this whole situation any more poorly then they did.

When my service manager handed me the car keys after his second and last failed attempt to fix my problem, he said 2 things that threw me:

1) My issue wasn't a serious one as the car was completely drivable.

When I told him that I would probably lose money on a resale, he said:

2) Chysler minivans were known for their weak transmissions and that hadn't stopped people from buying them second hand, thus Toyota resale value would not suffer.

This prompted me to setup the 5 internet polls where people could vote about the frequency of this issue and comment as to whether or not they would buy a second hand car with this issue.

Over 95% of respondants said they would not buy the car or would ask for a major price reduction.

So much for my service manager's ability in avoiding any insults to my intelligence!

I failed to mention that I also had the TSB ECU reflash for sulfur in the meantime too, but did not affect MPG like the MAF cleaning. Yes, MAF sensor is very delicate but well hidden in the sensor's plastic housing. Use pure acotone or comercial "electronic" cleaner. Could be a long shot but wouldn't hurt. My car had 2.5 years when I tried the cleaning.

So the purpose of the combined ECU flash and MAF sensor cleaning was to lower the overly rich fuel/air ratio at cold startup time that was resulting in excess sulfur (smelly) emissions. Right?

Have you noticed that with the lower emissions comes a lower peak idle rpm? Never above 1800?

Do you have the TSB number and did they flash your computer chip while still in the car or did they swap your old computer for another computer?

Thanks

Hey, I just wanted to say thanks to everyone for replying and helping us out here. I just want to explain a few things real quickly to put things into perspective.

1)- My wife and I are not very knowlegable when it comes to cars and repairs. Our plan was and always is to buy our vehicles new and keep them until they are ready for the graveyard. Therefore, we spend a lot of money on properly maintaing our vehicles in hopes we will get a tremendous amount of milage out of them after we have them paid off. That is why we buy them with 3 miles on them, so that we know no one has driven them improperly. We are both very rational and responsable people. I will admit, with us buying the cars new and having 2 identical Corollas (One that worked right one that didnt), I dont think we could have comfortbly dealt with this issue if we had decided to keep both vehicles. We dont feel as though we got our moneys worth with the '04 because of the idle problem. I was however just fine with the '05.

2)- My wife just graduated from UMSL and is very close to starting her career. We are renters and have not yet purchased a home (plan to have a house by end of summer 06), therefore, both of the cars we have are our most valuable assets. This is not a 8 piece box of chicken we are dealing with here. Our cars are 5 figure assets and we are serious about them. We spend a ton of money on them and expect them to perform up to expectations. If I wanted a problem, I would have bought a used American car. I can only imagine how the Toyota arsehollies would have reacted if they coincidentaly received one of these defect cars. We spent over 25,000 dollars with our dealship and they wouldnt even sit down and answer questions with us personally after finding out about our car. I suspect the corporate executives dont want to take a "hit" on there bonus checks, so they elect to ignore these problems at the expense of future business.

3)- My wife and I are planing on starting a family within the next few years. Up until the past few weeks, it was money in the bank for us to buy a Toyota SUV as soon as the '04 Corolla was paid off, and go with 3 cars between the 2 of us. I mean we had discussed this many of times. There was a great chance all of our future vehicles would have been Toyotas AND purchased from the same local dealer. We are loyal customers. I have no problems switching to Honda.

4)- Seems like Toyota had a problem admitting fault. They never did admit that there was actually a problem with the car. They kept claiming it was "normal" and that really pissed us off. It felt like a slap in the face everytime. I certainly wasnt going to take responsability for the problem.They never could explain simple things such as why one did it and the other didnt,and why the one would do it at 29 degrees one day and it wouldnt the next at 30 degrees. If we had such a rare problem, they should have sat down with us and explained things to us, admitted they made a mistake in replacing the throtle body, and told us the truth. They contradicted themselves and lied. It seems like they literarly want to "snap there fingers" and make this problem go away. It got to the point of, how can I trust what they are telling me?How can I believe that this is not going to hurt my car or negatively effect things in any way. I know this now because of finding out from this forum.

Thanks again for understanding our problems here. I would much rather waste my stress on other things than my cars, I can assure everyone of that. That is supposedly why I bought Toyotas in the first place, so my vehicle would be one less worry. Ha! Thanks for letting me vent. The future looks like a pair of Civics right now!!!! Any good Honda boards anywhere? Anyone know what kind of deal I can get if I buy 2 cars at once?

Thanks again for understanding our problems here. I would much rather waste my stress on other things than my cars, I can assure everyone of that. That is supposedly why I bought Toyotas in the first place, so my vehicle would be one less worry. Ha! Thanks for letting me vent. The future looks like a pair of Civics right now!!!! Any good Honda boards anywhere? Anyone know what kind of deal I can get if I buy 2 cars at once?

Good luck with your future vehicles. Sounds like you are very unlucky, as Toyota is THE MOST reliable manufacturer, according to the surveys, but it can happen to any manufacturer. One of my wife's co-workers were loyal Honda buyers, but when they got a 2001 Odyssey, they had many problems, some rendering the car undriveable. I don't have the details, but I know there were several, because my wife had to pick her up! One of them was after the warranty was up. But then the big one hit - tranny failed at 60 some thousand miles. Yes, covered under warranty, but they were not happy at all, especially when they did a little research on the internet and found people had their replacement trannys fail also!!! (I admit I told my wife to tell her co-worker to check the internet about Odyssey tranny problems.) Guess what they drive now? Toyotas only! No problems with their 2005 Sienna.

I have to say some dealers suck, while others are great. Trying a different dealer could make all the difference in the world. And Toyota corporate - no better or worse than other makes, according to my research. But some say they are better, some worse, so.....

Anyway, good luck - I would caution you about the Civic - a first year redesign of any make, even Toyota & Honda, is likely to have more issues!

My best to you and your family.

Consumer Reports just did an analysis of first year redesign models. The conclusion was that buying the first year of a new or redesigned model is not a good idea with any manufacturer.

My 03 CE was an early build and I had quite a few minor glitches, mainly cosmetic but including the infamous sulfur "farts". My son's 03 was built 6 months later and only had 1 warranty repair, the "farts".

Honda's had a lot of bad luck with automatics in the last few years. Might go 5 speed if you buy one.

Again, I wish you God's belssings and may car problems be the worst troubles you encounter in life.

I failed to mention that I also had the TSB ECU reflash for sulfur in the meantime too, but did not affect MPG like the MAF cleaning.

Yes, MAF sensor is very delicate but well hidden in the sensor's plastic housing. Use pure acotone or comercial "electronic" cleaner. Could be a long shot but wouldn't hurt. My car had 2.5 years when I tried the cleaning.

So the purpose of the combined ECU flash and MAF sensor cleaning was to lower the overly rich fuel/air ratio at cold startup time that was resulting in excess sulfur (smelly) emissions. Right?

Have you noticed that with the lower emissions comes a lower peak idle rpm? Never above 1800?

Do you have the TSB number and did they flash your computer chip while still in the car or did they swap your old computer for another computer?

Thanks

"So the purpose of the combined ECU flash and MAF sensor cleaning was to lower the overly rich fuel/air ratio at cold startup time that was resulting in excess sulfur (smelly) emissions. Right?"

That would be my guess, but to be sure, ask that guy who wrote the ECU programming code.

I cleaned the MAF because MAF is the weakest part of emission system and gets fouled very easily.

"Have you noticed that with the lower emissions comes a lower peak idle rpm? Never above 1800?"

As I told before, I did not monitor cold idle RPM, it was somewhere near 2000 but I live in mild climate.

"Do you have the TSB number and did they flash your computer chip while still in the car or did they swap your old computer for another computer?"

I learned about this TSB on this forum, so if you use the search, you will find it. It was a flash, but the procedure called for replacement of some models of ECUs that were not flashable.

Interesting video. personnally I have never started my car and sat there just watching the idle go up and down. I usually let it warm up whil I write down my date and mileage, then I drive off. I would think it unusual but not too bad a problem. It is not stalling and not increasing the idle beyond control. It seems like a small fluctuation and like many have said is probably your idle control portion of the electronics. I don't know that it would have any significant affect on your gas mileage. If the dealer can't or is unable to fix it, what can you do? People are still living and driving with their Corollas with the same problem. I guess they have settled on imperfection.

I have an 04 corolla..I'm from north carolina but go to school in seattle and mine has done it ever since I bought it, only on colder mornings though, it will rev at 2,000 and slowly return to mornal idle as the engine gets warmer. I never really considered it a problem...the way I see it is that the engine revs higher at start up on cold mornings in order to heat up the engine faster.

I have an 04 corolla..I'm from north carolina but go to school in seattle and mine has done it ever since I bought it, only on colder mornings though, it will rev at 2,000 and slowly return to mornal idle as the engine gets warmer. I never really considered it a problem...the way I see it is that the engine revs higher at start up on cold mornings in order to heat up the engine faster.

It is normal for an engine to idle faster when first started. What this thread is about is on some Corollas the idle seems to be gradually creeping up and then falling back down to normal. It is as if it was searching for a setting. It appears like a feedback loop in a computer system making corrections to get back to normal, but the variance is greater than what should be. It is a temporary condition that ocurrs when it is first started and the temperature outside is on the cold side. It does not happen to everyone. It is being addressed because it needs attention by the manufacturer (Toyota) so that they will do the research and repairs on everyones cars that are affected at no cost to the consumer.

 

 

..... mine has done it ever since I bought it, only on colder mornings though, it will rev at 2,000 and slowly return to nornal idle as the engine gets warmer.

For all those who are not sure if they really have an identical problem or not, please listen to the following recording of the noise. The colder it is, the longer the pulsing lasts (up to 60 seconds). The time between pulses also increases as the temperture is lower because the colder oil increases the time for the engine to fall from the upper rpm ceiling (2300) to the lower rpm floor (1800) and back.

A typical event usually lasts twice as long as the abreviated recording. Link to this post and click on the mp3 attachment at the bottom of the paragraph.

http://forums.genvibe.com/zerothread?id=20409

It definitely does not sound normal. Anyone else who has a similar sounding car let us know.

I do.