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01 Corolla Burning Oil


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Hello, first post here. Could use some help.

79,000 miles, bought used, no clue if the oil was changed regularly. New plugs new wires.

Burns 1 qt every 300 miles. Ran a compression test and get 190-200 PSI on all 4 cylinders. Does smoke a little out of the tail pipe, but not excessive. Tail pipe has a bit of build up on it. Does not leak oil while the car is off, yet my right drive axle does look a little shiny, so it may be possible something is leaking out of the pulley's and then the axle is spinning the oil off while it runs. Not sure though, I haven't dug into the car far enough to get a close enough look.

Oh and this may be another problem, but I get occasional misfires or similar lag under hard acceleration, and only under hard acceleration.

I am assuming the rings and valves/seats are good due to the successful compression test. I am having a hard time figuring out where the oil is going. Only thing I can think of is maybe a bad exhaust valve guide or a pulley leaking. I have read other threads and will check my PCV tomorrow, but am curious as to how this might affect oil consumption? I am moderately knowledgeable when it comes to cars but not enough so, and always looking to learn more.

Any thoughts? All help or even random guesses are appreciated.

ever_green

Hello, first post here. Could use some help.

 

79,000 miles, bought used, no clue if the oil was changed regularly. New plugs new wires.

Burns 1 qt every 300 miles. Ran a compression test and get 190-200 PSI on all 4 cylinders. Does smoke a little out of the tail pipe, but not excessive. Tail pipe has a bit of build up on it. Does not leak oil while the car is off, yet my right drive axle does look a little shiny, so it may be possible something is leaking out of the pulley's and then the axle is spinning the oil off while it runs. Not sure though, I haven't dug into the car far enough to get a close enough look.

Oh and this may be another problem, but I get occasional misfires or similar lag under hard acceleration, and only under hard acceleration.

I am assuming the rings and valves/seats are good due to the successful compression test. I am having a hard time figuring out where the oil is going. Only thing I can think of is maybe a bad exhaust valve guide or a pulley leaking. I have read other threads and will check my PCV tomorrow, but am curious as to how this might affect oil consumption? I am moderately knowledgeable when it comes to cars but not enough so, and always looking to learn more.

Any thoughts? All help or even random guesses are appreciated.

2000-2001 corollas are notorious for burning oil. i have 2000 corolla but im really lucky no leaks so far. i don't drive it often though it has about 60k miles. anyway what's the mileage on the engine? 1 qt every 300 miles is bad however the problem can be fixed by simply replacing the leaky gaskets. This maybe costly but i dont think you can pass emission tests without fixing this oil burning issue. so either get rid of it for fix the engine.

reduce oil burning:

http://www.aa1car.com/library/oil_consumption.htm

Hello, first post here. Could use some help.

 

79,000 miles, bought used, no clue if the oil was changed regularly. New plugs new wires.

Burns 1 qt every 300 miles. Ran a compression test and get 190-200 PSI on all 4 cylinders. Does smoke a little out of the tail pipe, but not excessive. Tail pipe has a bit of build up on it. Does not leak oil while the car is off, yet my right drive axle does look a little shiny, so it may be possible something is leaking out of the pulley's and then the axle is spinning the oil off while it runs. Not sure though, I haven't dug into the car far enough to get a close enough look.

Oh and this may be another problem, but I get occasional misfires or similar lag under hard acceleration, and only under hard acceleration.

I am assuming the rings and valves/seats are good due to the successful compression test. I am having a hard time figuring out where the oil is going. Only thing I can think of is maybe a bad exhaust valve guide or a pulley leaking. I have read other threads and will check my PCV tomorrow, but am curious as to how this might affect oil consumption? I am moderately knowledgeable when it comes to cars but not enough so, and always looking to learn more.

Any thoughts? All help or even random guesses are appreciated.

Possible leak culprit may be the tensioner O-ring. You should have a look at the serpentine belt and check for cracks or excessive wear as well. I would also look under the fill cap for signs of sludge or excessive varnish build up. Clogged PCV valves are a common culprit, cost about $10 and are easy to replace. For that cost, I prefer to simply replace rather than clean. You may have an oil burner as well. Many 8th gen Corollas burn oil. Amounts vary. Your consumption sounds too high for burn off. Likely you have a burner and a leak somewhere, tensioner O-ring is my guess.

Mine is also a burner and burns a significant amount of oil. I've gotten used to its thirst and simply check and top up regularly to keep it full. You may be burning oil due to a clogged PCV valve, but you may also have the "sticky rings" syndrome many 8th gen have. Design defect makes the rings prone to sticking, and when that happens consumption starts. No known solution guaranteed to work short of an expensive rebuild, which is unnecessary, as the consumption will have no effect on the lifespan of the engine so long its regularly topped up.

There are various things that can be tried to reduce consumption, but the first thing to do is check the PCV valve and find and fix the source of the leak.

Edit: even though mine burns significant oil (averaging a quart every 1,200 miles this summer, though it'll decrease when temps drop and winter comes), you would never know it as it doesn't smoke.

-Spyder

If you were leaking a quart every 300 miles( or even a1/4 of that) the under side your car and where you park would be dripping /soaked with oil.

Welcome to the oil burners club!

What you describe is typical of bad sealing oil rings( bad piston design).

You will read many different reasons for it here, and other places , but this is what toyota says is the problem and the fix. : [/url]

 

http://www.toyotanat...iston+oil+holes

 

The main problem with burning that much oil other than the cost of oil , damaged cat and air pollution, is how easy it is to run the engine out of oil.

 

I had a cracked head on my 2000 and went searching for a used one. I looked at six heads at different places and all but one showed signs of oil starvation( cam bearing surfaces badly scored , gouged, melted).

 

 

Yep. Plenty of possible things to try to reduce consumption, but none are proven to work for everyone. Among the short list of things I've compiled (but haven't tried all of):

- use of an upper cylinder lubricant such as MMO or tc-w3 in fuel. These not only lube the upper cylinder, but can also slowly remove carbon deposits. May free the rings up, which may reduce consumption if the rings aren't also worn or damaged;

- use of an HDEO like Rotella to clean the engine out. Similar idea to the above, but different approach and the two can be combined.

- removing the plugs over night and soaking the pistons in a solvent like MMO or Seafoam. This is a more direct application of the first idea.

- using an oil that is more resistant to burn off and/or thicker.

- switching to a high mileage oil like MaxLife; can be combined with the previous idea (by using a thicker grade).

A sampling of things that I've come across, though not complete. There is also the ultimate solution when you've tried enough of the above and nothing's worked: look for sales on oil and stockpile. Keep a few quarts in the trunk, check it frequently, and add as needed. As long as it never runs low the engine, inspite of stuck/worn rings, can live a very long life as long as its oil thirst is properly quenched (or you hit on something that reduces it).

-Spyder

I like the piston soak and replace the PCV valve idea, even though it is a manufactures defect on the rings.

At about 100,000 miles, I went from burning almost no oil(less than half a quart every 3000 miles) to a quart every 1000 miles. This happend in less than 3000 miles.

Switched to Rotella and in about 6000 miles my oil burning came down to the level it had been. Before I pulled the engine it had 207,000 miles and still was not burning oil.

It would seem the Rotella worked for me.

When I tore down the engine it was fairly clean, just a thin coat of brown carbon/ varnish, no sludge, no deposits except for a very small amount on one side of the oil pan. I used dino oil and changed my oil at 3000 always.

I have torn down alot of engines and this was clean as engines go.

My oil ring oil groves had a hard brown carbon build up ( the same material that covered the engine in a thin coat ,just thicker), but my piston oil holes ( the ones under the oil rings) were open ,not totally, but open.

None of my oil rings were stuck , though the carbon in the ring groves was about a 1/16 inch thick and was behind and actually holding the rings out slightly.

Except for the factory coating on the pistons the old pistons measured( miced) the same as the new ones ( almost no wear) . The rings were the same way . The cylinders were about .0015 over the limit.

Spyder, it would be interesting to see what the measurements would be on a high milage oil burner. I wonder if all that oil would protect the cylinders better( like a 2 stroke).

I'm not sure at what point in its life this car began consuming oil. It was the typical little old lady driven car with mostly short trips, stop and go, and little to no highway. Throw in excessive idling in the winter with its remote start and a clogged PCV valve and you have the perfect recipe for sludge formation, which is where it was when I bought it.

I have replaced the PCV valve, and with Pennnzoil Platinum on sale here recently, switched over to that on my last oil change. I also added in 12 ounces of MMO (about a 10% concentration) to help the Platinum along. Its possible in my case that, as in yours, a high detergent oil like Platinum or Rotella may reduce consumption. Mostly right now I'm concerned with cleaning the sludge out, so my efforts have been more focused there then on the consumption.

I did though, several tanks back, begin using tc-w3 2 cycle outboard motor oil in my fuel. It has some solvency and is a good upper cylinder lube, so I think it has potential to clean the piston ring deposits out and free them up. More recently I switched to MMO in fuel, it has similar properties but I think its a stronger solvent and less of a lube. Similar idea, I plan to run this for 3 or 4 tanks then switch back to tc-w3 again.

More recently I've been looking into a product called Lubro Moly MOS2 which is an anti-friction treatment. One 300 ml bottle contains somewhere on the order of 4,300 ppm of molybdenum disulfide. This is a proven anti-wear additive that different oils contain different amounts of (though not usually in the disulfide flavour). The most I've seen was in Redline. Some oils today have none, mine has very little. Moly works by plating at the microscopic level the pits in pistons, cylinder walls, camshaft lobes, etc. Net effect is less wear, and I have seen some say their consumption problems stopped after a period of using this. Its a well-regarded product by a German engineering outfit that also produces high end engine oils. Its compatabile with synthetic, dino, and blends and doesn't alter the properties of the oil its added to. Even if it doesn't reduce consumption, those that use it indicate their engines feel smoother and cold start easier.

I plan on picking up a bottle of it from my local Napa tomorrow and will add half a bottle (this will achieve the recommended dosing of 3-5% concentration) to my sump. Plan to use it every other oil change. Same outfit also puts out a product called Motor Oil Saver. They claim it reduces oil loss through leaking gaskets or burn off through ring or valve issues. I'm still researching this one. If I try it, it will be on my next OC this spring. I also plan to move upto 10W30 PP then from the 5W30 I'm using now, as the 10W looks more resistat to burn off.

Meantime I will be running an upper cylinder lubricant every tank, whether MMO or tc-w3, both for lubrication and deposit control. That's my current and near future plan to try and remove the sludge and reduce consumption at the same time. I'm a long ways away from calling it quits and just feeding it oil wholesale. Rotella is also on my list of oils to try as it has a nice detergent package as well and has worked for some. MaxLife has worked as well for others. Too many things to try to think about giving up yet. Despite their ring issues, these 1ZZ-FE engines are very stout and pleasant both to drive and work on.

-Spyder

Meantime I will be running an upper cylinder lubricant every tank, whether MMO or tc-w3, both for lubrication and deposit control. That's my current and near future plan to try and remove the sludge and reduce consumption at the same time. I'm a long ways away from calling it quits and just feeding it oil wholesale. Rotella is also on my list of oils to try as it has a nice detergent package as well and has worked for some. MaxLife has worked as well for others. Too many things to try to think about giving up yet. Despite their ring issues, these 1ZZ-FE engines are very stout and pleasant both to drive and work on.

 

-Spyder

I recently bought Rotella T5 10w-30 for my next oil change, which should happen imminently. I'll report on what happens consumption-wise. My last two changes, Valvoline MaxLife and Castrol GTX High Mileage (both 5w-30), were both a vast improvement over the regular dino oils I had been using. They both resulted in about 1 qt. / 800 miles. It was much worse just 9 months ago when I made the switch. It's about time to run compression numbers again, too. I'll probably get to that after the Rotella cycle is done.

At about 100,000 miles, I went from burning almost no oil(less than half a quart every 3000 miles) to a quart every 1000 miles. This happend in less than 3000 miles.

 

Switched to Rotella and in about 6000 miles my oil burning came down to the level it had been. Before I pulled the engine it had 207,000 miles and still was not burning oil.

It would seem the Rotella worked for me.

When I tore down the engine it was fairly clean, just a thin coat of brown carbon/ varnish, no sludge, no deposits except for a very small amount on one side of the oil pan. I used dino oil and changed my oil at 3000 always.

I have torn down alot of engines and this was clean as engines go.

My oil ring oil groves had a hard brown carbon build up ( the same material that covered the engine in a thin coat ,just thicker), but my piston oil holes ( the ones under the oil rings) were open ,not totally, but open.

None of my oil rings were stuck , though the carbon in the ring groves was about a 1/16 inch thick and was behind and acually holding the rings out slightly.

Except for the factory coating on the pistons the o\ld pistons measured( miced) the same as the new ones ( almost no wear) . The rings were the same way . The cylinders were about .0015 over the limit.

Spyder, it be interesting to see what the measurements would be on a high milage oil burner. I wonder if all that oil would protect the cylinders better( like 2 stroke).

Bent Rod, which Rotella were you using? My 01 Corolla with 118,000 mi is using at least a quart between changes. Not bad yet, obviously but would be grateful if you shared that tidbit with us.

ever_green

Man now I'm worried is my corolla gonna be a oil burner when it hits 100k miles? It's going 73k now and absolutly no oil burning. But my sister is going to be driving it soon almost everyday.

Rodenn, I used Rotella T 15-40 non synthetic.

Changed oil every 3000 miles.

I recently bought and added 1/2 a can of Lubro Moly mos2 to my crankcase. This is an "anti-friction" treatment, or more accurately, a molybdenum disulphide additive. Modern API SM oils tend to contain little to no moly, which is a very good anti-wear additive. HDEO diesal oils like Rotella are likely already high in moly (in which case I wouldn't recommend adding it). Moly, over time and due to the heat present at operating temperature, plates itself to the microscopic pits on the combustion chamber metals, forming a protective film. It may aid in better ring seal, thereby boosting compression and lowering oil consumption. Accounts I've read from users state smoother running, quieter engines, and (in a few cases, reduced oil consumption.

I plan to add 1/4 can as a maintenance dose to future oil changes while I trend my oil consumption over the winter. If its still not to a level I consider acceptable by next fall, I'm considering adding their Motor Oil Saver product as well, as preliminary research into this looks promising.

Another approach, inline with the piston soak method, is to alternate a soak in a solvent like MMO or Seafoam with a lubrication additive called LC20 from Lubrizol. The basic idea is that the solvents will break down upper cylinder deposits while the LC20 will lubricate the upper cylinder directly and help free the sticky rings up. This may have to be repeated several times to be effective. Were I to go this route, I would do one soak about 50 miles before the oil change. After the OC, I'd monitor consumption, and if no improvement (or not enough improvement) shorten the oil change interval and do a second soak with the other product (MMO the first time, LC20 the second time) again 50 miles before the OC. I'd continue this until oil consumption was where I wanted or I'd done 6 soaks (3 with MMO, 3 with LC20, alternating products each soak) total. Again, I may try this over next summer (before resorting to Motor Oil Saver) and aquired some good but cheap dino juice for those short OCIs (thanks to a good Walmart rollback on Quaker State Peak Performance).

All of the approaches mentioned in this thread show promise. I would not (and in my case, don't) take anything away from a Corolla that develops an oil consumption problem. First thing to check (and imho replace, as its a $10 part) is the PCV valve. Then pick an approach or combination of methods and monitor consumption. Also allow time for any method to work. Just as consumption didn't happen over night (the day after it left the factory), reversing the process often takes time as well. It may take a combintion of approaches and anywhere upto 10-20,000+ miles to see good results; but taking into account how long these engines tend to live for, this is only a small fraction of their lifespan.

-Spyder

Ever Green yours will likely continue to run fine. If yours was going to burn oil it would have started before now so you sound like one of the lucky ones who got a engine without issues.

Spyder here are some more good products to use.

http://www.auto-rx.com/ -oil treatment, the best treatment that I know of with top results compared to other treatments for countless people I've seen on several forums.

http://www.amsoil.com/storefront/api.aspx?zo=515729 -fuel treatment, highly recommended as superior by mechanics I know.

https://www.amazon.com/ATP-AT212-AT-205-Re-Seal-Aerosol/dp/B001J89Q98 -highly recommended as superior and it worked for me. It's also available at bumper to bumper auto, possibly other stores too.

Check your engine seals and see if any are leaking. Mine started leaking at 99k only while driving.

What I wonder is if anyone sells properly sized replacement rings that eliminate the consumption? If not then I also wonder if the rings can be honed down slightly to eliminate the problem, and if so where could one go to get that done?

Ever Green yours will likely continue to run fine. If yours was going to burn oil it would have started before now so you sound like one of the lucky ones who got a engine without issues.

 

Spyder here are some more good products to use.

http://www.auto-rx.com/ -oil treatment, the best treatment that I know of with top results compared to other treatments for countless people I've seen on several forums.

http://www.amsoil.co....aspx?zo=515729 -fuel treatment, highly recommended as superior by mechanics I know.

https://www.amazon.co...l/dp/B001J89Q98 -highly recommended as superior and it worked for me. It's also available at bumper to bumper auto, possibly other stores too.

Check your engine seals and see if any are leaking. Mine started leaking at 99k only while driving.

What I wonder is if anyone sells properly sized replacement rings that eliminate the consumption? If not then I also wonder if the rings can be honed down slightly to eliminate the problem, and if so where could one go to get that done?

Toyota says the oil burning problems are caused by the oil holes( in the pistons) under the oil rings becoming blocked with carbon.

Low oil flow doesnt cool that area of the piston or flush away carbonized oil after the holes are blocked.

The carbon then builds up to the point where it causes the rings to stick.

Also higher than target( design) temps( 160c instead of 120c ) on that area of the piston adds to the problem.

The fix is larger and more oil holes under the oil rings .

My new pistons have the improvement.

Great to know that Bent, thanks for explaining. I have been on corolla forums for years and that is the first I've heard the exact cause posted.

Sounds like the cheapest fix would be to use Auto RX to take care of the deposits and free up the rings. If that didn't work for whatever reason then the improved pistons would be next.

Do you have info or a link for those pistons so everyone here will know the brand or where to get them if they need new pistons? How much was your total cost parts/S&H/labor?

Great to know that Bent, thanks for explaining. I have been on corolla forums for years and that is the first I've heard the exact cause posted.

 

Sounds like the cheapest fix would be to use Auto RX to take care of the deposits and free up the rings. If that didn't work for whatever reason then the improved pistons would be next.

Do you have info or a link for those pistons so everyone here will know the brand or where to get them if they need new pistons? How much was your total cost parts/S&H/labor?

The pistons are the stock ones(for any 1ZZ) toyota sells now.

I talked to the Toyota parts guy where I bought them, and he told me there had been a few revisions since 2000 and that I had the latest ones.

They look almost identical, except that the new ones have twice the number of holes and the holes are twice the diameter.

The pistons are the same diameter as the old ones, but a gram lighter( probably from the extra material removed for the oil holes).

The old ones had two 1/16" holes on either side ( 4 total).

The new ones have four 1/8" holes either side ( 8 total) .

The set of pistons were $225 and rings $100.

Look here for more info on the oil burning and new pistons: http://www.toyotanat...iston+oil+holes

I am doing a total rebuild on the engine ,so I orderd all the parts for the rebuild together, and I am doing the labor.

I bought my parts at http://www.toyotapartscenter.net/ overall( parts/ shipping) they had the best prices. The service was GREAT( ask for John).

Dont order on line( call the toll free #) if you can help it , you will get much better shipping prices if you talk to john direct.

Since I was ordering thousands of dollars worth of parts I shopped around at all the online Toyota parts stores. Some had cheaper parts but the "mystery"/ very high shipping costs stopped me from buying at those places.

Great to know that Bent, thanks for explaining. I have been on corolla forums for years and that is the first I've heard the exact cause posted.

 

Sounds like the cheapest fix would be to use Auto RX to take care of the deposits and free up the rings. If that didn't work for whatever reason then the improved pistons would be next.

Do you have info or a link for those pistons so everyone here will know the brand or where to get them if they need new pistons? How much was your total cost parts/S&H/labor?

If you do a little searching on the 8th gen Corolla forum on ToyotaNation.com, there is a great description of the new pistons with pics and part #s. The author's name is Sam3365 or something similar.

ever_green

i still don't understand why my corolla doesn't burn oil, not that im complainin. just saying, a 2000 corolla shouldn't have the cylinder improvement. i have never smelt burning oil or seen it and i floor it quite often too.

Hit or miss it seems - some 1998-2002 Corollas don't burn any oil at all, others guzzle oil. Could it be the way the car was broken in? Or type of motor oil used? Oil filter choice? Oil change interval? Hard to say, so many variables are involved, be tough to pinpoint the true cause.

Still, there is a manufacturing change from the 8th gen to 9th gen 1ZZ-FE engines. If this was in response to oil consumption, we may never know for sure. The two generations 1ZZ-FE due operate differently - 9th gen transaxles are geared differently, revised camshaft profile, upgraded ECM - engines will turn more RPMs compared to the previous generation.

Doesn't mean that the 9th gen Corollas are immune to oil consumption - there are a number of threads out there where some 9th gen Corollas are guzzling as much oil as the 8th gen Corollas, even with the revised oil holes.

My 2002 is the same way - has a little more than 170K miles, bought when new. First 10K miles were on conventional motor oil (free oil changes from dealership promo), swapped to synthetic afterwards, and I drive the living tar out the car daily since. No babying the car, the car was designed to be drive, so I try and drive the lugnuts off. Mixed highway and city - commute in the DC Metro area, so some extreme driving conditions. Minimum of 80 miles a day for commutes - typically run between 15K-24K miles a year, depending on which car I take. Car presently doesn't burn any oil (knock-on wood). Car did loose a few ounces of oil when the timing chain tensioner gasket leaked, but hasn't lost a drop after that was replaced.

I should have said " toyota says the fix is" because I dont think that is the whole problem either.

What is the cheapest mod / band-aid Toyota can do ? Drill holes in the piston .

Do I really beleive that I can use any oil , any oil change interval, any driving habits I want now because of the modified pistons ?

NO

There are to many variables( engine design being one) , but I think the oil holes will help the problem.

I wont use dino oil in my rebuilt engine, except for break in. These engines do not do well with dino oil!

I laughed when I read my 2000 owners manual( bought the car new) and it said oil changes every 5000 miles.

I have used dino oil from day one,( 3000 mile interval always) and did not have a problem untill around 100,000 and then suddenly started to burn alot more oil( 1 quart every 1000 miles) between oil changes switched to Rotella and in about 6000 it came back down to normal( less than 1/2 quart every 3000).

Did the Rotell help ? It seemed to, but I dont really know for sure.

When I pulled my engine apart it was fairly clean, no stuck rings , oil holes in piston were open, no sludge, just a thin coat of "varnish".

I would like to know if any of these engines that have run synthetic oil from the begining, have oil burning problems( with regular oil changes ,I would guess no).

Fishexpo, I read that you have taken apart some oil burners. How were the rings, piston oil holes ?

I have only seen one post with pictures that show an oil burner with the rings clearly stuck.

I have read alot about wrong sized pistons , rings ect. I did not find that in my engine. All the mesurements were in line with the manual, given wear.

I've only played with one 1ZZ-FE that was a known oil burner, and a few more that were not - most of the oil burners involved a bunch of non-Toyota imports and mainly domestic ones (one Ford Taurus 3.0L V-6, older Quad-4 motors, Saturn 1.9L SOHC/DOHC, GM V-6, GM V-8, older carburated SB/BB GM and Mopar SB/BB/Slant6 engines, BMW, DSM, and Hondas).

That 1ZZ-FE for the most part - looked like it was in good shape, aside from consuming an excessive amount of oil (1 quart @ 150 miles). It didn't have any outward signs of being a oil burner - sludge, obviously scored or out of round cylinder walls (polished smooth), hard carbon deposits, etc. Some residue on the bumper, but it didn't smoke at all from the exhaust. Topend of the engine looked good - nice golden color, no heavy deposits, no big chunks or patches of sludge anywhere. It actually looked cleaner than my own engine (my pics on photobucket site in my sig - but that was probably all the additives this guy was adding to the oil to clean up the engine.

Looking at the piston, fair amount of carbon deposits (typical for an oil burner), rings did look good, though some were broken (oil ring side rails), which surprised me. Oil control ring (expander ring) looked OK, was still loose and was pretty flimsy - but not sure if they all are like that. Rings were not stuck, some deposits in the ring lands, but nothing that looked like it would compromise the specs. Before the engine got torn down - compression test showed it was still good 185PSI+ each cylinder. Plugs were toast after 6 or 7 months - about 5K-8K miles tops before they were completely clogged with ash and oil fouled.

Unfortunately, didn't take any pics - as there the engine cleaned prior to it being pulled down. You name it - it probably was run through the engine. AutoRx, Seafoam, MMO, Rislone, Gunk, BG products, Rotella, ATF, diesel, etc. So the real culprit probably got "washed" away. Be nice to get a hold of an engine that is consuming an excessive amount of oil, but had nothing done to it other than topping off the oil level. Then on teardown - should be able to spot the problem.

Since many have reported a sudden switch to heavy oil consumption, especially when the mileage starts hitting 100K+, I'll just wait it out and see if it my car starts too. But since I used only synthetics and monitor my oil with UOAs, I'll probably be waiting for some time.

Yup, 5000 miles changes - and that was when they lowered it too - used to be longer. The book in my '96 Camry recommended 7500 mile intervals on conventional oil for normal driving conditions. We stuck with that interval and only recently dropped it to 5K on high mileage oil because of the miles on it (switched to 5K drain intervals when the car had 280K miles on it and started to use 1/2 quart of oil between the 7500 mile intervals). Now it drinks a few ounces between the 5K intervals, but has more than 300K miles on it.

Fish do you prefer a company for UOA's over others and if so who are they? I've seen people have bad experiences with some companies getting samples mixed up between customers and loosing samples.

Blackstone labs has been good to me. www.blackstone-labs.com

I haven't gotten any mixed up reports, funky test results yet. You also get the technician's comments on what they see in the sample and their recommendations - ie, a person is doing it instead of a machine loading samples. I also send in two samples at a time - get the results within days - some cases I get the results within 48 hours of sending the sample via USPS.

Standard analysis is $25, TBN is another $10 - so it is not the cheapest UOA shop out there - but if I send in only 4 samples a year max - not really a big deal to save a few bucks here or there, since I know I'll get good service and fast turn around time on the results.

Plus you can order the sample containers for free - takes 1-2 weeks to ship them to you.

Ok good deal thanks.



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