unusual engine oil consumption

The oil probably goes into the coolant, via head gasket leak or cracked block.

No it is not normal. Do you ever clean or wash your engine when it is hot? Please mention oil change frequency and brand/type of oil.

I change oil every 3 months or ~3K miles. I have no idea how you "wash" the engine? Sometime, I do change oil when engine is hot, so is oil but not frequently. I have not notice any dark color in coolant.

This is the post in a couple of weeks asking about disappearing oil in a

2001 Corolla, and I suspect that the causes are the same. I do not recall seeing a response from the other poster saying whether he discovered the cause or not, but I suspect that the cause is a leak.

I don't like being harsh, but if you'd searched the group before posting you'd see we just covered this on the same car.

Short answer: make sure your oil pan bolts are at the proper torque.

being harsh, but if you'd searched the group before posting

I did search this NG, no good hit, especially the one mentioned by Ray. I do change oil myself, I do know whether there is a leak or not.

being harsh, but if you'd searched the group before posting

search this NG, no good hit, especially the one mentioned by Ray.

I mean if there is a leak from bolt.

Until someone is able to find a leak or identify the cause of the oil loss, I recommend that you note and keep track of the date and odometer reading whenever you add oil, the viscosity of the oil that you are added, quantity of oil added, and the type of driving done prior to adding the oil, such as mixed city and highway, mostly city, etc. Hopefully a pattern will emerge from the information that can help us identify where the oil is going.

Not necessarily. I had this same condition on two Corollas.

You won't see drips in your driveway or where you park. It leakes out the 'seal' between the oil pan and the engine when the car is running and the oil is at pressure.

condition on two Corollas.

What does it mean if I keep adding oil to top it? If I do the oil change, will the "extra" oil will be released or it will stay there cause more problem later?

There are several possibilities -

1) You have a leak that only is "active" when the car is running. Therefore the oil is distributed along your route of travel. Usually you would see some sign of the leak on the outside of the engine even if you don't see it on the ground. If the rear seal is leaking, it might show up on the transmission bell housing instead of on the engine proper. 2) You have an internal leak and the oil is either moving into the cooling system, or into the intake system. If the oil is leaking into the cooling system, the engine coolant should be discolored. If it is leaking into the intake, it might be harder to find. 3) Your positive crankcase ventilation system may need to be serviced. If the PCV valve is not operating properly, excessive pressure can build up in the crankcase and force oil out. Or a clogged PCV valve can allow excessive oil to be sucked into the intake system. PCV valves are cheap, have yours checked. 4) Your engine is consuming oil. It is normal for any piston engine to consume some oil - in fact it is necessary to lubricate piston rings and valve guides. Engines that don't appear to use any oil are replacing the oil with contaminants that have escaped past the piston rings (water, unburned hydrocarbons, etc). Most companies don't get excited about oil consumption until he consumption exceeds one quart per thousand miles. If you are only using 1 quart in 1000 miles on a 6 year old car with 78,000 miles, I don't think you should worry. I do recommend having the PCV system checked, and looking for external leaks.

Ed

condition on two Corollas.

All depends on how fast the leak is. IIRC, you said a quart in 200 miles? THat's a bit. I'd check it every week, depending how many miles you drive.

I have a Supra that leaks oil just sitting there. I have a puddle in my garage. I add a quart every two weeks. But, I have a gauge, too, so I can keep an eye one it.

Try the simple stuff...loose bolts or filter, check the seals (visually), etc. Also, if it's an automatic, check the ATF. It shouldn't be black, or even brown, really. If it is, you mak have a leaking seal between the engine and the tranny.

condition on two Corollas.

said a quart in 200 miles?

thanks, I'll check what you and Ed suggested.

I believe oil consumption is common and understated. My 95 Corolla 1.8 started using oil when it was 6 years old and 50k miles. It is the valve seals on cylinder 4, and can be verified by spark plug deposits. Since and now, the car uses 1 quart in 400 miles. No visible smoke, passes California smog but the rear bumper is white and shows black soot. I get a low speed miss after 6 to 8k miles, have the plugs changed and all is well again. The fix is easy. REbuild the head for whatever the cost or buy a case of oil now and then. You choose.

I will trade in 1999 Corolla pretty soon and I like to have my 2001 Corolla keep running for another 100 years. I hope that this oil "leaking" problem will not cost outrageous head repair bill later. As long as it keeps running, I am OK to keep adding oil once a while.