Oil smell from back of engine with engine running?

**Mike02A4** · 09-09-2008 03:09 PM

I get a smell of oil from the back of the engine, I can also sometimes smell it while driving. What is back there that I can check for, for being a possible cause? With the engine off, I did not smell it. Its the same smell you'd smell if you removed the oil cap after the engine has been running and hot. Its an 02 1.8t.

**dougyfresh** · 09-09-2008 03:17 PM

Your oil leak is most likely:

1) leaking valve cover gasket in the back of the cylinder head
2) leaking cam tensioner gasket (very back of cylinder head on the intake side)

Have you replaced the rear coolant flange back there? How about the rear coolant sensor? Those two items are also notorious for failing and decided to die on my 2002 back around 75,000miles.

Run a few searches in the B6 A4 forum for those items and you'll find a few DIYs and other such good info for fixing the problems. I just saw a thread yesterday about the cam tensioner gasket.

**Mike02A4** · 09-09-2008 03:43 PM

No leaks back there, just checked. The previous owner had the cam seals replaced under cpo in 06. Looks like they replaced the valve cover too, no leaks.

Coolant flange and sensor have been changed.

Anyone else have any ideas?

**Audi Skate Snow** · 09-09-2008 03:45 PM

bottom oil return line from turbo.... check to see if that is leaking.

**dougyfresh** · 09-09-2008 03:50 PM

Originally Posted by Audi Skate Snow

bottom oil return line from turbo.... check to see if that is leaking.

Oh yeah, I forgot that routes around the back of the head. It might be leaking at the turbo and dripping back towards the back of the head. Good call Charlie!

It connects to the top of the oil filter flange on the driver side of the engine. A hard line from the turbo to the oil filter.

**Mike02A4** · 09-09-2008 04:32 PM

Where exactly is that? A picture would be helpful, thanks

**ewytt** · 09-09-2008 05:08 PM

I think i have the same problem as you but a much larger leak

**bwoy1981** · 09-09-2008 05:22 PM

Originally Posted by Audi Skate Snow

bottom oil return line from turbo.... check to see if that is leaking.

Mine is leaking.. is it a matter of just tightening it up or should I try changing the gasket then re-tightening it.

**Audi Skate Snow** · 09-09-2008 10:40 PM

Originally Posted by bwoy1981

Mine is leaking.. is it a matter of just tightening it up or should I try changing the gasket then re-tightening it.

For sure check it out, alot of the times they get a little hair line crack right at the neck (where it bolts up). you have to look really close becuase it wont look like it but if you slightly move it you will see oil come out.

if there are no cracks try replacting the gasket and making sure its tight... but becuase dont make it to tight to where you snap the bolts :)