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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Backfire on Cold Startup

  • Thread starter Thread starter 1991RWHP
  • Start date Start date Sep 17, 2009

1991RWHP

New Member
Oct 8, 2008
59
0
0
Illinois
Sep 17, 2009
#1
  • Sep 17, 2009
  • #1
If i start the car up for the first time after the car has been cool ... it backfires for a few times out of the intake. When the car warms up a little bit it goes away and the car runs fine. Any Suggestions?


Also, on cold startup .. the car has a hard time staying alive... the rpms drop a ton and sometimes it even dies. After i start it up, the same thing happens.



Both situations happen on COLD START ... any suggestions on what to look for?

Its a built 306.. H/C/I .. Mild Ford "F" Cam. I will take any suggestions, thanks for your time!
 

93project

Active Member
Apr 21, 2009
549
52
38
El Paso, tx
Sep 17, 2009
#2
  • Sep 17, 2009
  • #2
Bump- I had the exact same problem with my 93. TFS stage 1 cam, ported GT40 heads, intake, etc. etc. I'll be carb'd on the new engine but I always wondered what caused the issue.
 

poulrais

New Member
Mar 25, 2009
44
0
0
Sherbrooke. Quebec, Canada
Sep 18, 2009
#3
  • Sep 18, 2009
  • #3
Mine did something like this at one time and the cause was a bad signal from the O2 caused by oil coming from my crank seal leak getting into the O2 plug under the car. It had something to do with the closed/open loop cycle at startup and the ECU wasn't getting the right info from the O2 sensors. Cleaned the O2 wiring harnesses and the problem disappeared.
 

ALMOST STOCK

Founding Member
Sep 23, 2000
1,250
41
88
CA.
Sep 18, 2009
#4
  • Sep 18, 2009
  • #4
I had the same problem, found out I had a vacuum leak.
 
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