[arkie6]

Originally Posted by Bimmer_Engineer

So I changed my oil yesterday and I took the opportunity to take the undertray off and look at the intercooler connections...

The connection bw the intercooler and the lower charge pipe had a few drips of oil on it. I think this is indicative that it could be the Boost leak. I didn’t break the connection because I needed to put the car back together and I don’t have a new o ring anyway...what do you guys think?

Oil in the intercooler and associated piping isn't uncommon and is typically due to the PCV vent pipe on the boost side circuit dumping directly into the turbo inlet pipe at the back of the engine. That is unless you have an oil catch can on this line. The PCV system on this engine does a poor job of separating oil vapor from the air stream so the oil vapor gets carried throughout the intake tract.

[Bimmer_Engineer]

Originally Posted by arkie6

Oil in the intercooler and associated piping isn't uncommon and is typically due to the PCV vent pipe on the boost side circuit dumping directly into the turbo inlet pipe at the back of the engine. That is unless you have an oil catch can on this line. The PCV system on this engine does a poor job of separating oil vapor from the air stream so the oil vapor gets carried throughout the intake tract.

I’m not talking about oil in the intercooler. I’m talking about oil drips on the c clip between the intercooler and the lower charge pipe...on the outside of the piping. The only way I can envision oil getting on the outside of that connection is if it’s leaking...

[Bimmer_Engineer]

Originally Posted by RSL

Right, but my point is, just because that's where the oil drips are, doesn't mean it's coming from that connection or even necessarily from a boost leak. There's a good possibility it is, but could be higher in the charge pipe, from BOV/DV if venting to atmosphere, etc. It could also be something old, unless you know for a fact that it's not.

You're not even sure if you boost have leak to fix yet, so just be careful about getting sucked into chasing something that might not exist. If vacuum lines don't help (still think those should be done regardless and make sure to check or bypass the plastic tubes running over the valve cover), pressure/smoke testing to find leaks is faster and cheaper than replacing random bits on hunches.

Understood...thanks. I’m doing the vacuum lines anyway...I’m just doing them piecemeal as I have time. I had the charge pipe off last week and I didn’t see any oil on the outside. That seal is only like $15 so I’m probably just going to change it and see if that helps...will let y’all know...

[JuniorB]

The oil outside the pipe by the connections is a good indicator that if leaks, air leaks. Those stupid orings don't last a long meaningful life.