White smoke from exhaust, no coolant loss

[avarfang]

I have a 2003 A4 1.8t with 151k miles.
Two months or so ago I started noticing that the car was smoking quite a bit in the morning on cold starts and city drives when stopped. I assumed it was just condensation/vapor as the weather has been quite cold.

The last two weeks it's been more apparent, but I also had a coolant temp sensor issue and the car would not warm up at all so I didn't drive it much. After replacing the sensor, it turned out the thermostat was stuck open as well. Now that I've replaced both the coolant temp sensor and the thermostat, the car warms up to temperature as normal, but there is still plenty of white smoke/ There is no apparent smell to the smoke.

From searching around online, it sounds like the white smoke would be indicative of coolant burning off and either a blown head gasket, turbo, or the oil cooler? However, I have had absolutely no coolant loss the past few months, when I drained the coolant to replace the thermostat there was no oil in it whatsoever, and when doing the oil change last weekeend, the oil was clean and had no coolant in it either. So I am a little baffled and looking for ideas on what to check next to start ruling things out? I plan on getting a harbor freight compression tester to hopefully completely rule out the head gasket. Not sure on what to check regarding the turbo/oil cooler though.

Also, the PCV hose connection on the TIP is broken off, and I am waiting on the new TIP in the mail. I remember reading in one of the threads that a faulty PCV system could cause white smoke too, but not exactly sure how?

[MikTip]

Is the white smoke steam or burning oil?

Could be the turbo....

[avarfang]

I'm not sure what the white smoke is. It doesn't seem to have any bluish tint to me, but I don't think it's just steam as it is pretty thick. What would be a way to determine whether it is the turbo or not?

[MikTip]

Any noticable loss of oil via dip stick level?

[avarfang]

Yes, I went through 3/4 of a quart in the last 4000miles, however I've had a slow leak from the oil drain plug and a leak from the valve cover so I accounted it to that? When I pulled of the intake hose to the throttle bodu there was a bit of oil in there too, which from my understanding is due to the PCV system too?

[SJorge3442]

sounds like your pcv is clogged which is pumping oil vapors into the intake system and forcing them to be burned, hence the oily throttle body. Then again I could be wrong. I know the 3.0 doesnt push the pcv system into the intake (most domestics stick it in the intake, post filter) but if the 1.8 does do this, which I think it does, which is why people run oil separators/catch cans, then this could be doing it. However, you would be burning oil and that burns blue.

[avarfang]

Thanks for the tip Sjorge3442. It turns out it was simply just a completely clogged pcv valve. After replacing it it took a little while for the smoke to go away, I guess there must have been some oil left over in the exhaust system. Now there is absolutely no smoke anymore. Also did a compression test and it was between 155-160psi on all 4 cylinders so great news on that end as well :)

[jacobsen]

Sounds like a blown Turbo homz, pull your lower intercooler pipe and see if oil drains out of it.

[schmally]

I replaced a cracked check valve and installed a DIY catch can. So far mine has been doing a shit ton better

[SJorge3442]

Thanks for the tip Sjorge3442. It turns out it was simply just a completely clogged pcv valve. After replacing it it took a little while for the smoke to go away, I guess there must have been some oil left over in the exhaust system. Now there is absolutely no smoke anymore. Also did a compression test and it was between 155-160psi on all 4 cylinders so great news on that end as well :)

Nice! Glad I was able to help. Make sure those pcv lines are in tact. If not, replace em. Not worth the loss of performance for a silly cracked line.

[avarfang]

Sounds like a blown Turbo homz, pull your lower intercooler pipe and see if oil drains out of it.

Turbo seems fine, checked for shaft play when I was replacing the TIP, and there wasn't any at all. Smoke went away after replacing the PCV valve like I said and everything seems good now.