Start up

[tanz45]

Mine does the same thing but only on cold start ups to around 1800 RPM. Goes down if i tap the gas pedal. Once it is warm it is fine.

May be a bad IAC or 02's aren't getting a good reading maybe and calling for fuel. IDK, helps my truck warm up faster.

[graysilverado5.3]

Idk man thats strange have you took a scan of your tune?

Haven't had it scanned, asked my tuner about the problem, he did not know either but he told me another truck does the same thing. The owner of that truck has tried everything and still nothing.

Mine does the same thing but only on cold start ups to around 1800 RPM. Goes down if i tap the gas pedal. Once it is warm it is fine.

May be a bad IAC or 02's aren't getting a good reading maybe and calling for fuel. IDK, helps my truck warm up faster.

I replaced one 02 already cuz it was complety dead. I'll check into the IAC.

[Ran06chevy]

is it just high reving to warm the motor up? mine revs high when it first starts but then drops with in seconds back down to 1200 when its super cold and about 650-700 warm

[graysilverado5.3]

Its just when I turn it on initally, the rpms jump up then within seconds it goes down back to normal.

[farmtruc]

if it's not a vac leak, i know what it is

[2boosted]

Spread the word.....

I have change IAC, TPS, Accel Cable, Reworked the TB, and nothing !!!!!

[graysilverado5.3]

Thats what I was thinking, spill the beans on what it is, lol
btw, i plan on going turbo soon, will this have any effect on the turbo or could cause damage to it?

if it's not a vac leak, i know what it is

[farmtruc]

well i think this is it, if the truck is 100% mechanically sound, do this to the calibration.

under spark tables, set Startup Flare to -64, see what that does.