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Old 03-23-2015, 10:22 PM   #1
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Default White smoke from tailpipe (worse when hot) - opinions?

99 NB, 75K mi on stock engine, 5K on DIY t3 ebay turbo @ 8-10psi. Reverant MS2. The car runs and drives alright (for a beginner's tune, startup kinda sucks), has plenty of power and spools great. I called Savington this morning and he said my compression #'s were bad, but I need to perform due diligence before I eat ramen for 2 months during a rebuild.

How did this begin? Every couple of weeks i'd be stupid enough to get stuck in San Francisco traffic and after idling/barely moving for 15 minutes the smoke would start to pour out. Then driving off, it seemed to go away. I couldn't even reproduce the smoking by leaving my car idling in the driveway for half an hour then driving it up and down the block trying to simulate traffic and decel in gear trying to pull oil through vacuum (thought it was PCV or valve seals). Then a couple of days ago in traffic, it happened again and is now much worse:

Cold engine - no sadness

Cool engine w/ revs - some sadness

Warm engine revs - so much sadness that the camera falls over

Sometime between "occassional problem" and "undrivable" I did change the oil from castrol 5w40 synthetic to Rotella T6 5w40

I've replaced the PCV valve with the 323GTX unit and tried stock routing (vc to intake manifold and open drivers side port) and 'unhooked' (plugged intake manifold and both valve cover ports open.

I pulled the turbo compressor inlet and outlet and they were both dry, medium shaft play but no more than when the unit was new

Spark plugs all look dry

No fluids are low but it's smoking bad enough that I can't drive around for 1,000 miles to find out. Oil is at the correct level but I may pull out .5 quart to make sure of no turbo oil drain hose blockage.

Compression test today but no leakdown yet
Dry & Wet
#1 - 165 190
#2 - 162 180
#3 - 162 188
#4 - 180 188

The smoke is white but it doesn't smell sweet and headgasket-coolant problems I've seen in the past smoked more. And why would it go away after idle smoke for weeks, even when I boosted the **** out of it? Any opinions on whether valve stem seals could smoke as bad as the videos? There is no puff upon startup after sitting. Pull the head? Pull the motor?

Last edited by JoeWagon; 03-23-2015 at 10:33 PM.
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Old 03-24-2015, 04:52 PM   #2
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Pretty sure I talked to you on the phone yesterday. After our call, I recalled a customer with a locost who had a similar problem - random oil smoke from the exhaust after periods of idle. He tore his motor down and found major scoring in one of the bores. The wet test results you got are sort of what I expected you to see.

Time to pull the shortblock. It's done.
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Old 03-24-2015, 10:12 PM   #3
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Mine had a similar smoke. Turned out to be brake fluid from a leaking master cylinder being sucked passed the booster into the intake. Mine did smoke constantly though. You would be holding brake pressure in that stop/go slow traffic.
Take off the booster line and plug it going to the manifold to prevent vacuum leak. See if the smoke goes away after a few minutes. It took mine about 10 minutes to burn clean.
It may be worth checking before you pull the engine because its easy.
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Old 03-25-2015, 08:55 AM   #4
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With those compression numbers I wouldn't blame the brake booster
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Old 03-25-2015, 09:02 AM   #5
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you need new ringlands.
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Old 03-25-2015, 12:26 PM   #6
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Time for the mad scientist to rip apart the block and replace the PISTON RINGS you fried
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