Black Oily soot in Plenum & Throttle Body- what is this?
#1
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Black Oily soot in Plenum & Throttle Body- what is this?
First I noticed a little puddle of oil underneath the fuel injectors on the R. hand side the the engine on the enigne block. Now I notice a black oily soot inside the plenum and throttle body. My car has been smoking at startup..which I believe is being caused by bad valve stem seals. Can anyone tell me what is causing all of this??
Car / Engine Specs:
1988 GTA
350 (TPI)
130,000 miles
Thanks Guys!
Jacob
Car / Engine Specs:
1988 GTA
350 (TPI)
130,000 miles
Thanks Guys!
Jacob
#2
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Is the puddle near/under the egr connection to the plenum? The egr recirculates exhaust gases, so there could be some type of problem if with it. Maybe a leak even. The black crap inside the plenum is normal, but it shouldn't be liquid. Maybe you have a fuel leak that caused the carbon to become liquid like that?
#3
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It's not a liquid... just a "sticky" soot.
The little puddle of oil is right under the fuel rails.
Jacob
[This message has been edited by 88 GTA Notchback (edited July 07, 2001).]
The little puddle of oil is right under the fuel rails.
Jacob
[This message has been edited by 88 GTA Notchback (edited July 07, 2001).]
#4
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Car: yep
Engine: uhuh
Transmission: sure does
The puddle under the fuel rails is caused by oil creeping up the intake bolt threads.
This is why when assembling any engine that the intake bolt holes go through to the lifter valley, it is a good idea to use a sealant (Liquid teflon) on them.
------------------
ASE Mechanic/Machinist/Smog Tech
1999 NBM Trans Am
1986 Chevy 3/4 ton pick up
1981 corvette
1995 Kawi ZX6R
and 2 POS commuters...
R.I.P. #3
"He can see air"
This is why when assembling any engine that the intake bolt holes go through to the lifter valley, it is a good idea to use a sealant (Liquid teflon) on them.
------------------
ASE Mechanic/Machinist/Smog Tech
1999 NBM Trans Am
1986 Chevy 3/4 ton pick up
1981 corvette
1995 Kawi ZX6R
and 2 POS commuters...
R.I.P. #3
"He can see air"
#5
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I removed one of the intake bolts and it is oily. Man, I would have never guessed that.
Thanks dude. You just saved me from having a stroke.
Jacob
Thanks dude. You just saved me from having a stroke.
Jacob
#6
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Car: 86 T/A
Engine: 5.0 TPI
Transmission: 700R4
You might also, while you're digging around near the intake check the four center bolts for proper torque. They easily loosen and can leak and deposit in the manifold valleys.
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