Oil on my engine block, please help!

[g8rdmd]

OK, all, I was under my car today for routine inspection and a little maintenance. I noticed that the left side of the engine had a coating of oil gunked all over it. I snapped some photos--looks like it's coming from the manifold?? It spreads all the way to the mid- line of the engine, but does not cross to the right. I have had NO oil on the garage floor, no noticeable oil loss according to the on board computer. This is the first time I've noticed this, and I look under the car at least on a monthly basis...

Please help me, what am I looking at? What should I look for? What should I inspect? Is it possibly a manifold gasket? Please tell me it's not the RMS. These were the best pics I could take today, I can get more if you need different views...

[Loren]

If it were on the right side (as you sit in the car) I would suspect the oil pressure sensor -- but if it is on the left then that will require more thought.

Perhaps leaking cam actuator or cam cover?

[g8rdmd]

Yeah, definitely isolated to the driver's side of the engine. I'll have to look over the service manuals--is the cam cover accessible without pulling the engine from the car?

[Loren]

For looking and some repairs you will need to take the intercooler off on that side (same procedure as a spark plug change).

For now I would clean as much of the old oil and grime off - then run the car to get good and hot -- then look for the source of the leak(s).

[g8rdmd]

For looking and some repairs you will need to take the intercooler off on that side (same procedure as a spark plug change).

For now I would clean as much of the old oil and grime off - then run the car to get good and hot -- then look for the source of the leak(s).

OK, I'll start there--thanks a lot for the tips Lorern!

[g8rdmd]

Today I decided to get into things to try and see where this mystery oil is coming from... I removed the rear bumper, left intercooler assembly, left tire and wheel well lining, air box, y-pipe and throttle body. Then I lowered the engine to give me the best view...

Here's what I've found so far. The pipe coming from the turbocharger into the intercooler had oil in it (see pic). Not a ton, but it was definitely present and seemed fresh-ish. Shouldn't this pipe be clean? Is it possible for the turbocharger to have an internal leak which is introducing oil into the air system?

That leads me into the second thing I found and that was gummy oil deposits in the throttle body. Again, shouldn't this be clean? It almost seems as if the deposits are gummy enough to interfere with smooth action of the throttle plate. In fact, the car occasionally stutters like it's starved for air and will sometimes stall--I wonder if this is the cause... Best way to clean??

The good news (?) is that I didn't see any leaks high up in the engine or coming off of any supply pipes. The oil pressure sending unit looks kind of dirty and may be leaking a little, so I will replace it (I have a new one on hand anyway). The side wall of the engine, plugs, O2 sensors, etc are clean of oil.

So, my plan while the car is apart is to replace the plugs and coil packs (with 997 coils), clean things up as best I can and get back on the road. I'm just shy of 60,000 miles, what other maintenance should I perform while I've got my baby torn apart?

[jpflip]

I love renntech :thumbup: Good job g8rdmd !!!! The deposit of oil in the outlet pipe of the compressor, if it is not a mpuddle of oil, can be consider normal. The throttle body is really dirty but again not dramatic....Of course a good cleaning is required!

[g8rdmd]

I love renntech :thumbup: Good job g8rdmd !!!! The deposit of oil in the outlet pipe of the compressor, if it is not a mpuddle of oil, can be consider normal. The throttle body is really dirty but again not dramatic....Of course a good cleaning is required!

Thanks again ;) I know we have a lot of cross-posters between here and 6speed--both of these sites are treasure troves of information for the DIYer :thumbup: I still don't really know where the oil is coming from, I'm hoping Loren will have some more ideas for me :notworthy:

Edited August 26, 2012 by g8rdmd

[jpflip]

Good reading for you: http://www.6speedonline.com/forums/996-turbo-gt2/164757-oil-y-pipe.html

[g8rdmd]

Good reading for you: http://www.6speedonline.com/forums/996-turbo-gt2/164757-oil-y-pipe.html

Great link with some interesting tidbits. Thanks!

[wvicary]

You will always have blow-by on a engine and that is what dirties the throttle body unit. It's also normal to have some oil in the turbo charger pipes which will accumulate over time/use.

You need to look toward the top of the engine for the source of the leak, by looking at your pics, it's all ran down the cylinder head.

No check engine lights or code history?

[g8rdmd]

You will always have blow-by on a engine and that is what dirties the throttle body unit. It's also normal to have some oil in the turbo charger pipes which will accumulate over time/use.

You need to look toward the top of the engine for the source of the leak, by looking at your pics, it's all ran down the cylinder head.

No check engine lights or code history?

No CELs, no codes. With the airbox, y pipe and throttle body out, and the engine dropped, I've craned my neck in there with an LED light as best I can--for the life of me, I can't see any wetness anywhere. The oil pressure sending unit was a little gunky, so I replaced it since I had a new one standing by anyway. I'm hoping it's not a head gasket or something else that I can't see/get to without the engine being removed. I reeeeeaaaaally don't want to have to have the engine removed....

[wvicary]

Can you post some pics of a wider view of the oil leak? The next step is to clean the area, run the engine and watch for leaks. Just be patience as sometimes these leaks are difficult to solve.

[g8rdmd]

Can you post some pics of a wider view of the oil leak? The next step is to clean the area, run the engine and watch for leaks. Just be patience as sometimes these leaks are difficult to solve.

I'll see what I can get picture-wise. Since the car is apart right now I'm going to change the plugs and coils, fuel filter and really give it a good cleaning to get the grime off. Then I'll put it back together, leave it up on jack stands and let it run for a bit to see if any oil shows itself...