Truck is 2000 k2500 with 7.4. 180K miles. Installed a new distributor while I was replacing leaking intake gaskets. The distributor I installed had a non adjustable tab on it. When I got the distributor installed to what I felt was the correct position I wasn't able to line the tab up with the threaded hole in the intake. The distributor more or less rests right against the intake plenum on 454 vortecs when the cap and wires are installed. Instead of pulling the dizzy, I removed the non adjustable tab and installed the oem tab and turned the distributor not more then a bolt hole over to install the hold down bolt.
The engine starts and idles really well. However, I can feel it stumbling or missing off idle at a constant rpm say 1k and up. The strange thing is, I don't have any codes showing a fault with cylinder misfires or cam sensor correlation. The truck seems to be running descent but you can definitely tell its missing if your in park and just running the engine off idle.
My timing shows 19 degrees at idle roughly 600 rpm.. it will go up above 50 on the freeway if I goose it and then settle out in the upper 30's
Do I need to go in and reinstall the original tab and readjust the distributor to line up with the bolt hole or think about looking at something else??
Does anyone have a 454 fuel injected vortec that happens to know what there timing is at idle??
On another note it does have a 411 pcm installed so, I'm not sure if that has anything to do with it. The PCM was tuned by lextech and I'm sure he knows what he is doing. Also ran pretty descent before all of this.
I also checked my vacuum while it was running. that seemed to be around -20psi and would increase when revved until it was revved really high.
thank you for any help.
Tracy
The engine starts and idles really well. However, I can feel it stumbling or missing off idle at a constant rpm say 1k and up. The strange thing is, I don't have any codes showing a fault with cylinder misfires or cam sensor correlation. The truck seems to be running descent but you can definitely tell its missing if your in park and just running the engine off idle.
My timing shows 19 degrees at idle roughly 600 rpm.. it will go up above 50 on the freeway if I goose it and then settle out in the upper 30's
Do I need to go in and reinstall the original tab and readjust the distributor to line up with the bolt hole or think about looking at something else??
Does anyone have a 454 fuel injected vortec that happens to know what there timing is at idle??
On another note it does have a 411 pcm installed so, I'm not sure if that has anything to do with it. The PCM was tuned by lextech and I'm sure he knows what he is doing. Also ran pretty descent before all of this.
I also checked my vacuum while it was running. that seemed to be around -20psi and would increase when revved until it was revved really high.
thank you for any help.
Tracy