V8 6.0L

[birddog]

I have a 2000 GMC sierra 4x4 with a 6.0 liter V8. I am having difficulty figuring out why it is not starting properly. When you crank it over it does not fire immediately like it used to, I have replaced both the fuel pump and the fuel filter and still it starts bad. Once started it will idle high then almost stall. After that it runs great. I was told that it could be the IAC motor. Any suggestions?

[99Silver6.0]

I have a 2000 GMC sierra 4x4 with a 6.0 liter V8.  I am having difficulty figuring out why it is not starting properly.  When you crank it over it does not fire immediately like it used to, I have replaced both the fuel pump and the fuel filter and still it starts bad.  Once started it will idle high then almost stall.  After that it runs great.  I was told that it could be the IAC motor.  Any suggestions?

 

<{POST_SNAPBACK}>

 

 

 

You may want to check out your pressure regulator. Its on the fuel rail on the drivers side. Since you replaced the fuel pump, that would rule out that little check valve in the pump that would let fuel in the rails bleed back into the tank. You can take the IAC motor off the TB, its held on by 2 srews. See if its all caked with crap. The pintle could very well be frozen up. Is your SES light on?