Engine irregular when cold

Tiny
GAZY
  • 1994 ALL OTHER MAKES ALL OTHER MODELS
  • 80,000 MILES

When the engine is cold, it starts ok but at idle it is irregular, shakes and seems to backfire. It turns at between 900 & 100 RPM. After 5 or 6 minutes, when it's warm, it stabilizes and works fine the rest of the time. Changed spark plugs because they were sooty and black. Changed fissured distributor cap and spark plug cables. Smoke at tailpipe is white. Still searching for the cause.

Do you
have the same problem?
Yes
No
Sunday, October 30th, 2011 AT 12:16 AM

4 Replies

Tiny
MERLIN2021
  • EXPERT
  • 17,581 POSTS

Excessive white smoke is usually a blown head gasket or cracked head. Do a block test. Check steal seal. Com for more info. In your case as it heats up it could be sealing the leak a bit.

Was this
answer
helpful?
Yes
No
Sunday, October 30th, 2011 AT 4:41 AM
Tiny
GAZY
  • MEMBER

Thanks Merlin, will check both gasket & head. Locally somebody said I should also check the Idle Control Valve, what do you think? There is also a strong gasoline smell in the exhaust smoke. Again, thanks.

Was this
answer
helpful?
Yes
No
Sunday, October 30th, 2011 AT 6:37 PM
Tiny
MERLIN2021
  • EXPERT
  • 17,581 POSTS

Idle air control if defective will cause sralling hot or cold. Do a compression test and also take vacuum readimgs, you may have a bad intake manifold gasket, that reseals when it expands during warm up.

Was this
answer
helpful?
Yes
No
Monday, October 31st, 2011 AT 8:16 PM
Tiny
GAZY
  • MEMBER

Thanks again, will do. Cheers.

Was this
answer
helpful?
Yes
No
Monday, October 31st, 2011 AT 8:38 PM

Please login or register to post a reply.

Other Engine Backfire Questions