Start up

[graysilverado5.3]

Almost every other time I start my truck, the rpm goes up to around 2200rpms then goes back down normal. It does not matter if truck is cold or hot. Truck is an 05 5.3 bolt ons, cam, stall, tbss intake. Any idea what could cause this?

[Botlfed]

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

[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.