Fox T-Bird/Cougar Forums

Technical => Engine Tech => Topic started by: White85GS on September 17, 2013, 04:34:37 PM

Title: Sputtering/stalls first start of the day
Post by: White85GS on September 17, 2013, 04:34:37 PM
Like the title says, it will only do this the first start of the day, 2nd start, it'll idle a little high, then come down to normal like 30 sec or so later. After this, it's fine all day long. If I give it gas after that first start, it won't die. What should I be checking?
Title: Sputtering/stalls first start of the day
Post by: TheFoeYouKnow on September 17, 2013, 04:52:09 PM
Check fuel pressure on that first start, and check fuel pressure leakdown.
Title: Sputtering/stalls first start of the day
Post by: White85GS on September 17, 2013, 04:55:53 PM
These cfi's don't need to be primed like a carburetor does, do they? I know that they have a higher fuel psi than a carb, but still lower than multi port FI.
Title: Sputtering/stalls first start of the day
Post by: TheFoeYouKnow on September 17, 2013, 05:44:27 PM
No, check pressure and report back.
Title: Sputtering/stalls first start of the day
Post by: White85GS on September 17, 2013, 06:06:38 PM
What usually causes leakdown?
Title: Sputtering/stalls first start of the day
Post by: softtouch on September 17, 2013, 06:41:20 PM
Try tapping the gas pedal before you crank.
The 5.0 CFI has a fast idle step cam like on a carb. The cam can't move to the fast idle step with the spring tension of the throttle linkage on it.
Title: Sputtering/stalls first start of the day
Post by: White85GS on September 17, 2013, 07:07:02 PM
Actually, I did pump it a few times once, I know your not supposed to do that with FI, but it didn't sputter or die when I started it.
Title: Sputtering/stalls first start of the day
Post by: White85GS on September 17, 2013, 07:53:10 PM
Soft touch nailed it, I checked my manual and is does infact say to start a 5.0 CFI the same way you'd start a carb'ed one!
Title: Sputtering/stalls first start of the day
Post by: jcassity on September 17, 2013, 10:57:35 PM
just goes to show how small the world is.

a JY  owner drives a CFI 5.0 and i told him the same thing yesterday, its odd but true that they kina act  like a carb

this guys CFI has the vac choke pull off assemly on the pass side of the  CFI
Title: Sputtering/stalls first start of the day
Post by: beast50 on September 17, 2013, 11:41:29 PM
how old is the fuel filter?  Cheap and easy to do, definitely would not hurt anything.