[EZBNME]

Engine hard to idle cold and has part throttle popping through exhaust if driving until warm. Really been bad since having temps in the 30s. Summers are fine. Quits doing this altogether after 130- 150 degrees. I use 30lb injectors W/pro-m bullet. Yes, I am highly modified running heads, intake, and a 576 lift HR cam with 232/240 duration. I 've already done the norm checking computer for codes and playing with timing and fuel pressure, etc. I wonder if reversion through the air meter is part of cause. Also wonder if the bullet air meter is more to blame. Is the 80 pro m that much better? I did install shield on one side of air filter to keep fan off off it and this helped. Any thoughts on this or is my cold start program that far off engine being modified?

[GTRaptor]

What year is your stang?

I would definately consider a chip for your ride, "recalibrated" Mafs (PROM and C&L) are not as reliable as a properly programed EEC.

Still have the EGR ?

[EZBNME]

Car is 87 with converted 89 A9L. I use an Autologic chip that turns EGR off, raises idle/ rev limit and no tuning. Engine should not be this hard to idle when cold. There are no air leaks. I've been told the bullet meters are not calibrated exact. I don't know. Shops want car overnight and $300 just to tune the cold start only. Using something like an eec tuner might work better for me. Thanks for reply

[NoSlow5oh]

My 95 GT is completely stock and it does that. I have no idea what it could be either, so if you figure it out, shoot me a message please.

[EZBNME]

My engine is running to lean throughout curve especially when cold. It is the bullet meter. I've always had part throttle ping due to lean fuel curve and air meter fooling computer causing timing to increase. The only way to fix this is to change the 29 point curve inside the computer. Kenne Bell offers a 90mm air meter with a chip included to correct this. I could also buy a Tweecer.