White smoke after tune up? Help!

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LegTurbo87
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White smoke after tune up? Help!

Post by LegTurbo87 »

Hey guys new to the forum but been a lurker for some time. I have a 94 5spd Turbo Wagon, ran great before other than a fuel cut at wot due to an unplugged pressure sensor and a funky idle from a clogged IAC valve. So the past few weeks this is what I've done:

Pulled exhaust manifold/Turbo/Intake Piping and downpipe.
Replaced both exhaust mani gaskets new.
Removed and cleaned IAC - replaced gasket with new one from subaru
Replaced downpipe gasket with new one from subaru
Replaced coolant temp sensor
Replaced PCV valve.
Re-attatched hose from pressure sensor to nipple on intake mani.

The only gasket I re-used was the uppipe one and I cleaned it real good. All gaskets and mating surfaces coated both sides with copper gasket spray.

So I get the turbo back in, maf hooked up, no piping connecting them yet as I'm still in the midst of installing my tmic but they are all plugged in. Downpipe not attatched yet so running open turbo so to speak.

long story short I start her up to see if she sounds any smoother and I'm getting all this white smoke from the downpipe exit from the turbo and from what seems like the exhaust manifold gaskets??? It also smells a tad bit gassy but that could just be from not being started for a few weeks in the cold? I turned it right off but could it be it just needs to run to burn off any crap in there??

Any help would be apreciated guys. Thanks in advance.
If we don't know life, how can we know death? ~ Confucious

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LegTurbo87
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Re: White smoke after tune up? Help!

Post by LegTurbo87 »

anyone??
If we don't know life, how can we know death? ~ Confucious

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vrg3
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Re: White smoke after tune up? Help!

Post by vrg3 »

If this has only been happening for a short time, I'd just give it more time. Yes, it very well could just need to burn crap off. Every time I do work like what you did I end up with some smoke for a little bit. It's probably just random bits of penetrating oil and stuff that gets into the engine and exhaust. Probably some of the copper gasket spray too. I'd reattach the downpipe and go for a spirited drive and see if the smoking persists.
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Jessekrs123
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Re: White smoke after tune up? Help!

Post by Jessekrs123 »

vrg3 wrote:If this has only been happening for a short time, I'd just give it more time. Yes, it very well could just need to burn crap off. Every time I do work like what you did I end up with some smoke for a little bit. It's probably just random bits of penetrating oil and stuff that gets into the engine and exhaust. Probably some of the copper gasket spray too. I'd reattach the downpipe and go for a spirited drive and see if the smoking persists.
This.

When I tuned up my engine, I cleaned some internals with cleaner and whatnot, and my car was spewing white smoke for a good minute or two. (I cleaned up just about everything that I could) Then it went away and I drive it everyday with no problems.
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1993 Subaru Legacy Sedan 5 Speed FWD Green (EG33 swap in progress)
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LegTurbo87
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Re: White smoke after tune up? Help!

Post by LegTurbo87 »

While were on the subject is there any reason i should be getting smoke from my exhaust gaskets still? Whats the torque specs for them?
If we don't know life, how can we know death? ~ Confucious

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Re: White smoke after tune up? Help!

Post by vrg3 »

The nuts holding the exhaust manifolds to the heads have a specified torque of about 29 ft-lb. Most of the rest of the exhaust fasteners have a specified torque of 26 ft-lb.

How long has it been smoking?
"Just reading vrg3's convoluted, information-packed posts made me feel better all over again." -- subyluvr2212
LegTurbo87
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Re: White smoke after tune up? Help!

Post by LegTurbo87 »

Just when i started it up to see how it ran, it was the first its been started since the repair and first time in about two weeks, no smoke before that. Its very white smoke and smells gassy. I shut it off immediately for fear that i'd damaged something. I dont understand how the mani gaskets can still leak i just put new ones on with copper gasket spray too. Im afraid if i torque them down anymore ill twist one off. Btw its not a stock mani its a custom u/e tubular 4to1 manifold.
If we don't know life, how can we know death? ~ Confucious

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Re: White smoke after tune up? Help!

Post by vrg3 »

If it's the kind of smoking that Jessekrs123 and I are talking about, it's not going to go away just by waiting; you have to run the engine. It'll can last anywhere from 10 to 100 miles, depending how you're driving.

And smoke coming from the exhaust manifold gasket doesn't necessarily mean that the gaskets are leaking. It could be stuff on the outside that's just burning off. And if your custom header is new, it's probably got oils from the manufacturing process all over the inside and outside.

Also, if a gasket is in fact leaking, you really shouldn't try to "fix" the leak by overtightening the fasteners. That can overcompress the gasket and/or warp some of the mating surfaces, ruining the seal.

Unless you have reason to believe something may have been damaged when you did this work (other than the simple fact that it's smoking), I suspect what you're experiencing is perfectly normal, and would suggest you put the downpipe on and test drive it.
"Just reading vrg3's convoluted, information-packed posts made me feel better all over again." -- subyluvr2212
LegTurbo87
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Re: White smoke after tune up? Help!

Post by LegTurbo87 »

Yeah I suppose I should just wait it out then, only issue is the car isnt on the road right now so guess I'll just let it idle till warm then rev it up a bit to get things burned off. Guess my neighbors will have to enjoy the smoke show, between this and the upcoming seafoam treatment they got to love me.
If we don't know life, how can we know death? ~ Confucious

Current Ride:
1994 Turbo Legacy Wagon (Work In Progress)
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