Excessive oil consumption in 2001 Corolla

Just got a Corolla, 2001, 5 weeks ago, have added at least 2 gal of oil since. No leaks under car, no blue smoke. What needs to be checked first. Is it a timing belt or chain on that model, there is oil leak around that area.

I am curious to know how many miles you have driven in those 5 weeks, because 2 gallons of oil is a HUGE amount of leakage/consumption.

The one thing in which you can take some comfort is the fact that this engine uses a timing chain, rather than a belt. Based on your description, it sounds like there is a leak in the seal around the timing chain cover. However, 2 gallons in 5 weeks sounds like an Exxon Valdez-size leak, which seems contradictory in view of your two statements that you see “no leaks under the car”, coupled with “there is oil leak around that area”.

It is very possible that the oil leak is only apparent while the engine is running and the oil pump pressurizes the oil, so you might want to observe the area around the chain cover while the engine is idling. Pull on the throttle linkage a bit to speed-up the RPMs and see if the leak becomes more visible.

Bear in mind that the car’s catalytic converter would likely prevent you from seeing the classic “blue oil smoke” from oil that is being burned in the engine. Or, more correctly the cat will do so until it is destroyed by having to process oil for a continued period of time. Thus, the sooner you can figure out and resolve the problem, the sooner you can possibly save the cat and reduce your repair expenses.

My theory at this point is that the engine in this car was very badly abused by the previous owner(s), and that you have both oil leaks and excessive oil consumption as a result of (pick one or more):

Lack of maintenance (excessively long oil change intervals and/or a clogged PCV system)
Allowing the engine to operate with a low oil level
Overheating that warped the cylinder head and scored the cylinders and/or led to a breached head gasket

I would suggest that you have a compression test and a leak-down test performed a.s.a.p. so that you can decide how to proceed with this car. If the engine is in as bad a condition as I suspect, it would be cheaper to get a “junk yard engine” than it would be to tear the present engine apart and fix all of the problems lying in the engine.

If this engine went for excessive periods without oil changes, even the timing chain may be living on borrowed time, so the sooner you get to the bottom of this problem the sooner you can decide how to proceed. Unfortunately, it appears that some unscrupulous person sold you badly-damaged goods and all you can do at this point is to limit the financial hit that you are going to take with repair or replacement of the car.

I sincerely wish you good luck, and I urge you to have your next car carefully inspected by a mechanic of your choice prior to purchase.

The Cheapest Easiest DIY Check Would Be The PCV (Positive Crankcase Ventilation) System. The Tubing Should Be Unrestricted Inside And You May Want To Consider Replacing The PCV Valve If It’s Easy And Inexpensive To Replace.
A restricted PCV system can cause both leaks and consumption. I really doubt this the problem, but it should be checked and hey, stranger things have happened.

Some folks are under the impression that these cars were susceptible to engine sludging more than some other vehicles. Others believe that engine sludge problems in these vehicles was caused by owner neglect. Frequent oil changes during the vehicle’s lifetime would go a long way in preventing this.
http://www.schleeter.com/oil-sludge.htm

CSA

2 gallons? Or 2 quarts?

I’d say you bought a car with a serious problem that the prior owner was well aware of and had decided to unload the car for that very reason. That’s a very common tactic and someone down the road ends up with the headache.
If you bought the car from a dealer the dealer is quite likely unaware of this problem because the person who traded it in is certainly not going to tell the dealer it’s losing more oil than a grounded tanker.

If it’s not the PCV valve then a quick test might be to connect a vacuum gauge as a check for abnormally low vacuum. (Meaning engine problems)
The necessary follow-up compression test can reveal if there’s a piston ring problem. Valve seals may allow excessive oil consumption but there is no test for those.

For what it’s worth, before buying a used car a compression test should be the one check performed at a dead minimum.

The early 1ZZFE all aluminum engines are prone to burning oil, here is a link that may described the problem. http://www.toyotanation.com/forum/archive/index.php/t-353286.html

…but…we still need to know if the OP added 2 gallons or 2 quarts of oil!

 Yeah but if she was burning 2 GALLONS OF OIL within 5 wks.....she wouldnt be able to see anything in her rear view mirror due to the massive cloud of Blue Smoke Billowing out of her tailpipe.....No?

 The other possibility is that you have a MASSIVE oil leak that only runs out while you are driving it normally....You could be pulling a "Spy Hunter" Oil slick maneuver when you are cruising down the road.... 

Are you sure it was not two QUARTS you used in that period? OIl by the gallon is not normally used to top up your engine. If two quarts, it makes sense, but you still have a leak somewhere that does nort show up when the car is parked. If the engine used that much oil, it would certainly blow blue smoke.

Welcome to the world of owning a '98-'02 Corolla with a 1ZZFE engine. I have seen a lot of these things burn a lot of oil (people usually just deal with it or get rid of the car so it becomes someone else’s problem), and have wondered what makes them use so much oil. Americar’s link makes sense, and this may well be the cause of this common issue. Since Toyota apparently felt the need to change the oil passages in the piston skirt since the previous design tends to get clogged with sludge and carbon, that is a strong clue that this is the cause of the oil burning problem with these engines. Now we have an explanation and a solution.

Have you checked the oil pressure sending unit for cracks/leaks?