Well, I wanted to take the 7 out for a bit before I parked it for the night. Now, I didn't get into full boost (engine is stock, has manual HKS boost controller which I haven't touched) at most 3-4 psi shifting at about 5k. I pull up to park it and smoke just started coming out the exhaust. It was blue, so my guess is that it's oil. Any ideas?

 

Sounds like blue oil... sounds like you may have bad or going bad oil seals. What is the weather like over there? If it never goes freezing change your oil to some 20w-50 and see if that helps.

 

is turbo on / a turbo if that can be damaged if this is n / a can be very light oil a heavier test

 

Have you thought of the oil seal in the turbo? It may or may not be the case but i have had them go out. When they did the vehicle would only smoke when I compression braked, or was in boost. It would smoke when i pulled it into my driveway as well because i compression braked down my street when i pulled it apart i found a decent amount of oil in the intercooler plumbing. May not be the issue with yours but it sounded familiar so i thought i'd throw it out there.

 

I drove it again yesterday and not a single cloud of smoke.

 

Interesting. Under the same driving conditions? I guess keep an eye on it and keep tabs on your fluid levels. Try to keep track of conditions each time you drive it so if it does i again you have something to go off of. Not sure what could cause this only intermittently.

 

Yeah it's pretty weird. I too thought of the seal in the rear of the turbo going bad. Anyone know of the model of the stock turbo on the S4? Going to rebuild it.

 

ht18s

 

Sweet thanks! So, the general range for a rebuild cost wise is about $400+?

 

I'm sure if you did it yourself you could get away with it being cheaper than that.

Although if you are interested, check out BNR. The guy rebuilds our turbos for $375, or for more money will upgrade them from stage 1 to stage 4. bnrsupercars.com

 

Alright cool. And here's a shot of my A/F ratio from the gauge. Quite a bit on the rich side.

 

^ I'm sorry but that tells me absolutely nothing lol. I need some actual AFR readout numbers.

 

Guess I'm definitely going to have to invest some $ in an ecu and do some logging.

 

Before you assume the turbo is bad, drive under boost without the oil cap installed. Smoke gone? If so, then it's a bad purge valve causing the crankcase to pressurize.

 

Okay, will do. Getting my car back from the body shop tomorrow. I'll check it out. Thanks for the replies fellas.

 

Just some extra info, the ecu is stock.