Fox T-Bird/Cougar Forums

Technical => Engine Tech => Topic started by: notorious1538 on March 14, 2006, 07:38:20 PM

Title: is this normal?
Post by: notorious1538 on March 14, 2006, 07:38:20 PM
when my engine reaches redline and then let off on the throttle, a puff of black smoke comes out? that normal?
Title: is this normal?
Post by: SLEEPER T-BIRD 87 on March 14, 2006, 10:37:40 PM
probly carbon build up.
Title: is this normal?
Post by: 5.0willgo on March 14, 2006, 10:41:52 PM
Keep taking it up to the redline and that little puff of smoke will become a plume.
Title: is this normal?
Post by: thunderjet302 on March 14, 2006, 11:53:04 PM
No! I'd check into it and see what going on. Smoke coming out of the pipe after a trip to the red line isn't a good thing.
Title: is this normal?
Post by: V8Demon on March 15, 2006, 04:20:13 PM
Checked your oil level lately?  Could be a number of things.  On the 3.8's the valvestem seals are known to go bad and will let some oil pass by.  You'll notice it at high RPM's and occasionally on start-up.  Could also be a spring or even piston rings........ Do a compression test.
Title: is this normal?
Post by: notorious1538 on March 16, 2006, 12:24:50 AM
all right thanks man. because it only does it at higher rpms and its not like a cloud or anything just a slight puff.
Title: is this normal?
Post by: 460 turbo truck on March 16, 2006, 07:24:54 AM
just cause i don't know, is it a 5.0 or a 3.8 ?

i do know that oil burns blue, and unburnt fuel burns black, sounds to me like somethings still trying to pour fuel in, or one of your cyls. isn't buring fuel like it autta.

does it do it under a load, or just like a quick rap up ?!
Title: is this normal?
Post by: notorious1538 on March 16, 2006, 09:43:39 PM
well its an 88 3.8 with 67000 miles on it. i dont think it does it under a load because my tranny shifts too soon. but it's black. not blue. i think it might be carbon buildup or unburnt fuel.
Title: is this normal?
Post by: cougarcragar on March 16, 2006, 10:26:31 PM
67k miles, eh? How long have you had the car? How often do you wind it out?
What kind of person owned it before you (old?)?

Maybe a good ol' treatment of Seafoam would help clean out that mill.
Title: is this normal?
Post by: Tbird232ci on March 17, 2006, 06:53:22 PM
Quote from: 5.0willgo
Keep taking it up to the redline and that little puff of smoke will become a plume.

Ive taken mine past redline and into the limiter a few times, and i dont blow smoke. Yet.....
Title: is this normal?
Post by: Billyf17 on March 17, 2006, 07:14:04 PM
It could be the fact that the PCM can't react that fast and is still dumping fuel into the cylinders causing an extreme rich condition which causes black smoke.
Title: is this normal?
Post by: 88cougarxr7 on March 17, 2006, 11:41:55 PM
its definetly something to do with fuel and not oil...

always remember-
White-water/coolant
blue-oil
black-unburnt hydrocarbons (raw unburnt fuel)
Title: is this normal?
Post by: notorious1538 on March 18, 2006, 01:10:59 AM
Quote from: cougarcragar
67k miles, eh? How long have you had the car? How often do you wind it out?
What kind of person owned it before you (old?)?

Maybe a good ol' treatment of Seafoam would help clean out that mill.


i bought the car back in august with 61000 miles on it. apparently some old person owned it before me. i do it from time to time i guess. but it's hard to tell how fast im revvin it since i dont have a tach :(