ExPatBrit

On other vehicles I have owned a blocked /malfunctioning PCV system can cause problems like this. Too high a pressure causes the oil to vent back into the intake and burns it off.

code58

I agree with both Blueridge and EPB. I have known of people who have had experience with Mobile 1 that was definitely not consistent with others under the same circumstances. (such as heavy consumption) Blocked PCV's can also cause heavy consumption as EPB said. And the oil isn't all turning to sludge, probably not much at all, but if sludge blocks the return passages and causes flooding where it isn't normally supposed to be, that can cause it. Sludge can also clog the oil rings (when excess oil is burned) and let the oil past and as hot as the Cat. Conv. runs, it doesn't always cause smoke at all. Also, though it probably isn't the case, oil rings seal oil and compression rings seal compression. They each are designed to do a specific job. I have seen the time when the compression rings were good, therefore good compression and the oil rings were bad, therefore oil consumption. Compression ring don't stop oil and oil rings don't stop compression. (that is speaking generally, not specific technically) My feeling is with the compression noted, that it is probably bad PCV or sludge. If it's sludge, AutoRX is your answer! That's my 2 cents and I'm stickin' to it.

shark13

Thanks for the additional ideas. I believe the PCV value is what was removed to get access to the rear left and middle spark plugs. Is there more to the PCV system than this tube? There were two things I noticed about that holes the PCV valve connected to.

One, the horizontal hole (upper hole) the the PCV valve connects to had a vacuum pull on it. It actually surprised me the first time I felt the vacuum as it slight pulled my finger towards it. When the hole was not covered the engine did not idle smoothly, but when I put my finger there it idled like normal. I assume I could test the vacuum pull here.

Two, the vertical hole (lower hole) the PCV valve connects to in the valve body was leaking a small bit of smoke (I'm assuming it's smoke because it had a burnt smell). Is it normal for gases/smoke to be inside the valve body area? I am correct in assuming this is oil burning?

I'll try to figure out which oil was being used as well.

Update: They were using Chevron Oil.

noku

Look here for info about your pcv valve http://en.wikipedia.org/wiki/Pcv_valve

Sent you a pm yesterday

blueridge

If it's Chevron non synthetic oil that they've always used then I'm voting for a sludged engine. PCV is possible especially on the pre 2001's with the cheap plastic valve. In 2001 they beefed up the PCV.

ExPatBrit

The OP said it was a 1999. So I think you are right on target.

Since the OP hasn't bought the RX yet, he has the opportunity to fix it prior to buying it or move on. If the rest of the vehicle is good it's worth a try.

The PCV valve is cheap as is an Auto RX treatment.

shark13

Thanks guys for all the great info. Between some initial advice, the compression test I did, and the further input I am feeling better about this vehicle. I was doing some research and I think I identified the black canister below the oil filter...is it possibly the oil catch can? I saw on another thread information about how the PCV and a catch can are tied together. Is it possible that the poor condition of the PCV valve causes excess oil to drop to the catch can. The catch can by the way is caked with oil on the outside and dripping some. It's the only place on the outside I can see oil.

frohboy33

Pull the valve cover and check for sludge before purchasing. I wouldn't touch it if it burned 1 quart every 3000 miles let alone every 600 miles.

salimshah

Picture/photo will speak volumes ... are you sure your oil filter is not leaking .. no-oring or two orings etc.

Salim

carguy07

What catch can?

code58

A qt. every 600 mi isn't good. A qt. every 3000 mi. isn't bad at all. I have owned a lot of new vehicles and while always changing every 3000 mi, have never used less that 1/2 qt. in that 3000. That's with different brands (of vehicles) even. Am I driving 'em too hard? I'm not an old lady about it, but I don't think I drive 'em too hard.

salimshah

The ones that I know used to be on steam locomotives. It was a bucket to catch the oil/grease drip and the poor guy had a miniture mop which was used to brush (or slop on) oil-grease on moving part. The lubrication system was not part of the engine.

I really want to see the picture ... and not the old movies.

Salim

thomas1

He is probably talking about the hYDRALIC engine shock mount which has some hoses going to it. That is below the Oil filter....

shark13

Here is a picture of the thing I was talking about. Doesn't look like a motor mount...but then again I've never seen one on a Lexus before. Can't figure out where the oil is coming from if not the oil filter?

code58

Yes, that is the motor mount (1 of 'em) and it looks to me like that oil has come from the mount, doesn't look like it's from the oil filter removal. A lot of cars have had "oil filled" mounts for quite a long time now. I think the term "oil filled" is a little misleading, they have oil in 'em to dampen the vibrations from the engine. Don't let the split loom running to it fool you, that is also supposed to be there.