when i go to start my truck in the mornings it will surge for the first 1 minute it is runnning then after that i runs fine. i have done the plenum,full tune up,fixed my header leak, and fixed the cracked pvc vavle hose and nothing has fixed my problems. i am running out of ideas? any suggestions? it has no check engine lights

 

On a cold start, the engine will run up to 1200-1000 RPM, and then slowly settle down to 'normal' idle. Is that what its doing?

 

no it will go to 1000 rpm and then sit there and surge for the a minute or two and then it will slowly settle down after it is done surging. i have cleaned the iac and that didnt help. it also has a hollow cat and i dont know if that will cause it to run like that when it is cold

 

Sounds like maybe a vacuum leak. Does it act like it is "hunting" for the RPM it really wants to be running at?

 

yea kinda but after a minute or two it runs perfects and the idle is steady

 

Hmmmm.... Might wanna do a search, and see if you can find any more information on folks that used the E3 plugs, I seem to remember a few members having issues with them, but, I really don't think that is your issue.... not even sure it would be a contributing factor....

If it only does it at cold start....... try having a look at fuel pressure first thing in the morning.... I know, its a reach......

 

i checked the fuel pressure while it was runnning and the fuel pressure stayed the same even when the truck started surging.

 

Might try cleaning the throttle body, including the IAC passages.....

 

i did all that when i had my intake off a few thousand miles ago.

 

How long has it been doing this? Did it start before or after doing the intake work?

Have you checked for vacuum leaks? (doesn't sound like that either though...... )