old96A4

I have a oil leak in teh back of the engine and I can;r see where it's coming from. I replaced the valve cover gaskets about a year ago,
not sure if those are leaking again or not. what typically leaks , what gaskets in the 3.0 engine?? are there cam gaskets or is that just in the 2.7 engine?
maybe I got cheap gaskets last time and they need replacing again.. I can't see anything to put my finger on it. just oil all over on the drivers side toward the back.
getting messy..

N_Jay

Try a vented oil cap.

Lowers internal pressure if the crankcase vent system is getting clogged.

arjun90

I second this, I believe it's Revision N. Check AudiUSAParts. Purchase a new PCV Valve from FCPEuro while you're at it. Lastly, make sure all the bolts on the Valve Covers are torqued equally. You'll want to also make sure the breather hoses are secured behind each valve cover.

old96A4

I did put a new pcv valve on. I'll look for the different oil cap. Re did the drivers side valve cover. Still leaking. Can't see back there

Prospeeder

Do not put a vented cap or you will have an engine light for lean codes. Its NOT designed for a vented cap, the system IS vented by using the crank vent valve. The leak your having is probably the cam housing on the back of the head, theres a strange metal and silicone gasket that can leak. Its also real common for 3.0 cars to have all of the breather hoses from the vent to the valve covers and the one down to the valley pan clog up. This causes the oil vapors to accumulate in the plumbing and not head back to the oil pan, and its then pulled into the intake and burned causing consumption. Putting a vented cap does nothing but try to mask whats wrong. Dont listen to these guys....

jcman

A vented oil cap is not the best solution for a closed crank case system, the best remedy is to clear out the breather hoses or replace them. Prospeeder is spot on!

And to add as mentioned, the excessive pressures can cause the cam sensor gaskets to leak along with issues on the cam adjuster that is operated by oil pressure via electric spool solenoids, a service bulletin was out about a certain cam adjustment code linked this to engine breather/oil pressure problems....I believe Audi's answer was a new seal inboard of the cam adjusters or new metal rings on the adjuster "at that point"...I'll try to dig it up to show, but in any event don't do Band-Aid repairs in this area.

N_Jay

Fixing the crankcase vent system is certainly the "right" way to do it, but putting on a vented oil cap works wonders till you get the rest fixed.

It certainly helps identify if you really have a bad seal, or if it is an excess pressure problem.

It is not going to cause a lean condition that is not there for other reasons. (The OEM vented oil cap is not a completely open vent, it just limits the pressure that can be built up.)

Prospeeder

If the system pulls in fresh air, yes, it will set lean codes, the vent valve will no be in a closed circuit and will open more than its suppose to, and suck harder on the crankcase, and draw in more fresh air, thus leaning the mixture out and setting a fault.

N_Jay

I'll let you know if mine trips such a fault. My daughter put about 4000 miles, (short and long trips) on it before the accident with no CELs.

Maybe while I am fixing up the rest, I will attend to what I assume is a clogged breather system. (Several small oil leaks after twice having the covered resealed)

jcman

N_Jay the 3.0 is a different bird of a C5 engine and a tad bit more sensitive with the crankcase vent system, this is one of the main issues with this engine that leads to the premature exhaust cam lobe wear primarily on the 02 and 03's because the "unattended" high crankcase pressures that diminish or counter-act oil pressure were it's needed in this area, the 2.8 has more blow-off areas in the valve cover.