7.4 vortex misfire

[Mike from OK]

2000 7.4 vortec in a c3500. This truck belongs to my son and I have been helping him work on it when he needs more than two hands. Shortly after he purchased it, the truck began missing and running rough. He replaced plugs, wires, cap and rotor. No better so he pulled the upper intake and found two lower intake bolts laying in the intake. Pulled the lower and replaced the gaskets, reassembled but it still had a misfire. Replaced the injectors, still misfiring. So now to the question, can the cam offset cause a misfire issue as I’ve described. Truck starts good, makes no noise just has a misfire. As the engine turns over with the starter it does sound like it may be out of time, but starts up and idles just shakes with the misfire.Engine compression is consistent at 135 psi. Thanks for your thoughts on this. Mike

 

[Cadillacmak]

That could be so many things! Its really nice to have a programs like HP tuner and VCM scanner so you can see what everything is doing. I think there are some cheaper ones out there also. It is ends up being the cheaper route than just replacing parts, and there are a lot of people on here that can help all the computer learning.

 

[Keeper]

Did reading the plugs tell you which cylinder it is?

 

[Mike from OK]

Did reading the plugs tell you which cylinder it is?

No. At that point, he was just doing a tuneup. All the plugs needed changed, but he didn’t keep track of the cylinder they were in.