Oil Leak but no puddles
 

2002 Base with 120K. Couple months back starting to smell burnt oil while driving. It was very faint and never any drops on floor. Now when I get to work after 30 minute commute there is a much stronger smell and some oil smoke wafting out from under the right side. Burning off the exhaust system. I see some light oil moisture around valve covers but no obvious leak. Still no puddles anywhere. Any tips or ideas on where it is coming from?

When you say right side, are you referring to driver's side for U.S.? I still get confused by the left/right side vs passenger/driver side - mainly as I've seen left/right used from both front and rear perspectives. If you are talking about the driver's side, I have something dripping a few drops onto an exhaust pipe on that side right in front or next to the wheel. It is worse for a bit after gunning it. It's not my AOS as I just replaced it. I bought sparkplugs, gaskets, and tubes + PCV (or whatever it is called in a Porsche) ready for install, but haven't had a chance to get in there and see with all the rain lately...

If you are referring to the passenger side, check the AOS. With car running, try to remove oil cap. If there is excessive vacuum, your AOS is suspect.

You can also access the top of the engine and look into throttle body for evidence of oil.

Other things..are you sure it's oil? A torn CV boot will fling grease all over the underside of the car including the exhaust.

At 120K You're spark plug tube o-rings likely need replacement if they haven't been done already. That's about the time mine started leaking, dripping on the catalytic converter and creating puffs of smoke wafting from under the right side.

Thanks for the replies. I will investigate this weekend. AOS and spark plug tube o-rings were what I was thinking......but the CV boot grease is also an excellent, outside-the-box possibility...nice one dghii

As my gramps always told me - right or left side is always as if you were sitting in the car (facing forward-duh) - doesn't matter what part of the ball you live on.

AOS would have smoke coming out of exhaust, not engine bay (if sucking oil into intake). Definitely get the pre-opened clamps from Pelican parts if doing the AOS. It makes putting the AOS back in a snap (or just much easier than trying to do it the old fashioned way). Replacing the AOS is not a bad idea for general maintenance as they go out often enough. (30-60k miles from what I understand). It is a bit more of a task than it seems - at least the first time. I was a complete virgin on mid-engine or anything Porsche when I did mine. It went out 2 weeks after I bought my car.

Mine have already been replaced once at 30K (from maintenance records) and I'm at 60k and it needs it again on the same side. Don't know if 2.7 has more issues with the tubes/o-rings or just my specific car.

Make sure you have some good angled attachments for your wrenches and do the spark plugs at the same time while you are there...

I have the same symptom as the O.P. I was hoping it could be the AOS because I could do that for $140. Then I was deflated by reiver saying that an oil leak can't be the AOS. Are you sure? More oil comes out of mine on a long right-hand turn at the track. A guy following me said it was coming out the right/pass side, not the exhaust.

I'm not a Porsche pro, but I will say that I replaced the AOS and the issue did not go away except for the oil that was being sucked into the intake. Mine leaks right (down) near one of the 02 sensors and burns off. After some spirited driving, I can watch it drip a couple of times by looking under the car on the driver side the into the exhaust area behind the wheel to see the burnoff. If it only happens on right turns, oil could be coming from somewhere else, but I don't see how it would move all the way from the passenger side to the driver side. Also, one of your hoses to the AOS would have to be bad. There were no external leaks on my bad AOS. Oil just bypassed the diaphragm and went into the intake and vacuum hoses. spark plug tubes and o-rings are a cheaper and easier fix IME, so better it to be that IMO.

It is always on the right/passenger side on mine.

I had the same problem. Spark plug O ring was the culprit.

Apparently my BMW dealership sees it as if you are facing the front of the car...which caused my confusion. Cheers

I replaced the AOS tonight and one spark plug tube. I don't think that either were the issue. The drips come off the wire for the o2 sensor on the right/pass side. That is not under the plugs. I didn't get a chance to drive it. Probably Fri - we'll see what happens.

How do you get the tubes out? I couldn't get a grip with my needle nose pliers. I got one out but broke it, so I didn't do the other two.

I hope you got all the broken parts of the tube out - if you didn't they are floating round in your cambox.....
People have been using a marine transom plug - if you use the search function you will see many pictures and a couple of alternatives..... heres a description from one of the posts by The Radium King.

It's a 1" diameter rubber puck with a flat washer on each side. a bolt runs through the puck and joins the two washers. as you tighten the bolt the washers come together and compress the puck. the compressed puck squeezes outwards and seals the plug in the tube.

Thank you. I had not read enough - just seen instructions to pull them out with a needle nose. How vigorously does oil push around in that area? Would it wash it to the filter?

It could be a cam cover leak. Not a big deal unless its a lot of oil. You can try slightly torquing the cam cover screws a little (very little). If you torque them too much you can damage the cover.