Strange Oil Leak

[Dave_s]

I have a 2000 Carolla that is leaking oil. I do not get a puddle under the car and do not get the smoke out of the tail pipe that would indicate an internal leak. I'm happy to hunting for the leak, but my first attempt was a failure (I put the car up on blocks and clibed under it waiting to see it drip). Any ideas?

[wrightz28]

Do you change your own oil?

I know sounds like a crazy question, but, sometimes the filter gasket can get caked on to the mating surface and remain there (or a portion of it) when the filter is being changed and cause a leak.

[Brian R.]

Originally Posted by Dave_s

I have a 2000 Carolla that is leaking oil. I do not get a puddle under the car and do not get the smoke out of the tail pipe that would indicate an internal leak. I'm happy to hunting for the leak, but my first attempt was a failure (I put the car up on blocks and clibed under it waiting to see it drip). Any ideas?

How much oil do you loose (how many miles per quart)?

[drew300]

I've put newspapers under a vehicle to get a clue where to look. Leave them there overnight.
Bad PCV valves can cause oil consumption.

[Dave_s]

The car is loosing about half a quart per 600 miles.

I don't change my own oil. I did not nortice any burn't oil near the oil filter but will check.

Why would a bad PCV valve cause oil consumption? Where does the oil go (I don't have a puddle under the car and no smoke trail while driving)?

I have not tried putting anything under the car to find the leak, but I dont have any stains under where the car is parked. There is a stain on the bottom of the car that I plan to clean off next week or the week after so that I can see if that is an "active" leak. I have a freind who thinks it might be the oil pan gasket, but that is a guess without having looked at the car. I don't think thats the problem since that should leave a puddle.

I would like to thank everyone for the replies. I will try to check back more often.

[drew300]

I had a Corona that had the oil pan loose every spring. I just tightened it. But it left a mark.
The PCV value sucks from the crankcase, to burn nasty vapours. If it's bad, (stuck open), it can suck oil too. The cat can burn the oil, so you won't see smoke. Check the price for a factory valve. It might be a cheap fix, and if it doesn't fix it, that's one thing to strike off the list. (keep your bill incase you take the car in for service.) I suggest a factory one as I've heard that some aftermarket ones aren't calibrated right. If I remember right the PVC valve in my truck was $3-$5 or so, so it's not much to invest.
Also, I'm told it's common to have the drain plug stripped, but that also should a mark.

[Dave_s]

I replaced the valve. I also checked the coolent for Oil. There was none. I'll let you know if it worked.

[GSS123]

Thanks for keeping us informed. Looking forward to see if the PCV valve replacement solved the problem.

[Dave_s]

Unfortunatly, the valve replacement did not due the trick. I'm going to climb back under the car over the next couple days and see if I can find an expanding oil stain. Anyone have any other ideas I can try?

[drew300]

If it's not dripping, it's got to be burning it. Where else could it go?
There's no oil in the coolant, and no coolant in the oil, right?
Maybe try topping up with 1 grade higher, like 10W-30. I'll assume you're using 5w-30. The slightly thicker oil should burn slightly slower.
I've read of some engines having trouble with sticking rings. Does anyone know if 2000 Corollas have this problem?

[Dave_s]

I'll double check for coolant in the oil. I may have checked the first time when the oil was just refilled. There is no oil in the coolant. I'm thinkin that the oil may be dripping on to the cat or something else hot and burning up before it hits the ground. I would expect to smell it though and I don't.