Might have a problem
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Tire Smoking Tranny Blowing Director
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From: Barto PA
Might have a problem OK every time I start my car cold it the idle moves around like 300rpms. Also sound like its missing. when it warms up it doesnt sound like its missing but idle still moves around. Car has been down awhile so I dont know what it could be. Any help would be great.
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From: USA
Re: Might have a problem Sounds like in cold weather the fuel trims are too rich at idle.
To confirm use a PCM scanner and scan the long term fuel trims. the lower the negative values are the richer the AFR is.
the MAF frequency should be around 2800 Hz and about 2-3 lbs a min of airflow with timing around 17 degrees.
If it was too rich it could also cause misfire since all the fuel is not getting burned so via the scanner look for any misfires of error codes.
To confirm use a PCM scanner and scan the long term fuel trims. the lower the negative values are the richer the AFR is.
the MAF frequency should be around 2800 Hz and about 2-3 lbs a min of airflow with timing around 17 degrees.
If it was too rich it could also cause misfire since all the fuel is not getting burned so via the scanner look for any misfires of error codes.
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Tire Smoking Tranny Blowing Director
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From: Barto PA
Re: Might have a problem Hmm thanks. Ill go out and see with the maft for now. I think my tps might be going to 0 for the idle thing but I sold my autotap(YA im dumb).
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From: Barto PA
Re: Might have a problem Update: My idle screw wasnt right so it couldnt come down where it want so that pretty much fixed the idle surging. As for missing that went away a little but when i free rev it it lags so Im thinking its still to rich. Have the maft set on -5%. So I might drive it around and see if it clears up. Thanks for the help
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Tire Smoking Tranny Blowing Director
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From: Barto PA
Re: Might have a problem Well took it out and it feels good. Man my turbos love this weather I only took it up to 4000 or so and it was at 4 psi but it felt like full throttle.
