The truck has a random knock , or rattle(sounds like a injector knock). But the problem it only does it once in a while, start truck it knocks next time start truck it doesnt rattle. It also does the rattle at a low rpm no load. Also other day the truck had to turn over lots before it would start, then has been good till today when it took a lot to start it again then it was good after that again. It is not showing any codes also. Any help would be appreciated. It is driveing me nuts. Just about ready to get rid of this truck, it is like a ex wife just keeps taking money from me.lol. My injectors where just rebuilt this summer with flux 1. They dont even have 10k on them yet.

 

Does sound like an injector.

But the first thing to do is remove the boxes and see if the issue is still there.

MikeyB

 

Are you sure its not just timming rattle?

 

Are you still running the factory lift pump?If so it could be on its way out.Anyway to verify fuel pressure?

 

I have removed all the boxes and chips, and i also am running a aftermarket lift pump from bd. The rattle is intermitent one time when you start its there next it is gone . And it does it a idle and low rpm when you put truck in gear it goes seems to go away after that only to come at idle again.

 

Does the truck run fine other than the noise? have seen a fca cause some rattle on mine but it also had a stumble to it with no code stored.Anyway to check RP?

 

You can also try unplugging 1 injector harness at a time with the truck running and listen to the differences in the sound of the motor.If you have an injector not working right you will here a difference in the idle between each unplugged harness.Or if you really want to dig in remove the valve cover and take 1 wire off each injector at a time at idle.If one causes very little change in comparison to the others it is the bad one.