kone

hi,

i just recently replaced the turbo on my 2001 AWM A4 B5 1.8t with a used k03 i got from a buddy of mine who said it wasn’t causing him any problems. my old turbo’s wastegate flap was shot and this new one feels much better, the only problem is that after taking the car for a test drive it started smoking white out of the exhaust. i assumed this was just coolant being burned off because i had a spill of coolant into the oil lines so i changed the oil again to no avail. on idle it smokes not a lot but enough for concern and sometimes after stopping it would honestly resemble a blown head gasket. could it be just burning off residual coolant that may have spilled in the intake system or something that just needs to be burned off or is something actually wrong here.

thanks

Cybersombosis

Hm. Did you touch anything other than turbo related during your install? When you say spill of coolant, where exactly did you spill? Seems odd that it would keep smoking if it was just a small spill.

White smoke would point to coolant in the combustion chamber. Coolant mixing with oil either through the head gasket or the oil cooler but with the oil cooler, you usually see oil in the coolant reservoir and may be just a coincidence at time of install.

For a head gasket, check compression to see if there is a leak. For the oil cooler, look on internet on how to test it. Report back what you find.

kone

I had to remove the coolant feed line and in the process it all gushed down the oil feed line. anyways my plan was to put the old turbo back in and see if the smoke persists. the new turbo was a used one and it had some inward and outward play so i’m guessing that the turbo seals were on their way out and when i installed it and pushed 18psi through there it was too much to handle. bit of a bummer because the old turbo has a worn out wastegate flapper so it peaks at about 10 psi at redline with almost no boost until around 3k but ill try adjusting the wastegate rod until i can source a new turbo.

Cybersombosis

I’ve been reading and the only way for coolant to get into the intake of the turbo is for the turbo body to be cracked. The coolant doesn’t come in contact with any part of the intake.

kone

okok so this whole thing was a huge PITA, ill leave this here for anyone experiencing the same thing as me. basically, I went with a used turbo with unknown mileage because the wastegate was rock solid (little more play in the turbine than mine had but it wasnt huge). after installing and getting on the boost a little, the smoke started. sometimes it would be light, sometimes it would smokescreen the entire neighbourhood. after putting the stock turbo back in I concluded that the turbo seals of the replacement turbo went bad because of the mass amounts of smoke. weirdest part about it was that my coolant level wouldnt go down, but its possible i just wasnt driving the car enough to see the level change. stayed up until 3am to put the stock turbo back in and adjusted the wastegate and shes boosting how she should, took it straight to the track.

TL;DR: dont be dumb