1990 police truck in progress but need some help please

the truck has a quad shock front. i have a set of headmen headers on it but the hit the springmonut and i think maybe the frame rail. whitch cause a lot of vibration in the truck along with the knocking of the exaust against the leaf spring mount. has anyone had this problem and what did you do or is there headers out there that will not hit.( they where really hard to get in might not be the right ones could they be for a two wheel drive)

Also at low speeds under light acceleration it seems to go and then hesitate and then go. like it bucks back and forth and it is and automatic. never had that happen befor?

and last but not least it has a cherping sound when it warms up like the belt is bad but it is new along with a new tenisoer pully. not sure what it is but it soulds like a pully of some sort.


please help me i love this truck and i have a lot of money in it but i just want to fix the same things... thanks again for all your help

please i really need some help

I have a 90 K1500. I can't help you with the quad shocks setup since I have no experience with that.

Low speed hesitation could be:

- a vacuum leak
- bad EGR valve or solenoid
- bad IAC valve
- leaking fuel injector

It would be a good idea to put a scanner on it and see what the ECM thinks is going on (i.e. IAC counts, BLM, 02 sensor, knock counts, etc).

Besides the tensioner pulley, there is also an idler puller which has a bearing that can go bad. An automotive stethoscope can be used to pinpoint the source of the sound.

//2000CAYukon