Hello all, I am needing some help figuring out my issue. My truck is a 1998 GMC 3500 4x4 7.4 9200lb gvw. I rebuilt the engine and installed a comp cam XR264HR14, shorty headers and 36lb injectors. Also did the 0411 swap and had it tuned by blackbear. After everything has been installed, I can get the truck running but not well. After some months of diagnosing, fixing and swapping parts I still cannot get it figured out. The problem is that it is basically dead on 4 cylinders, or it is over fueling on 4. Runs very rough and pops through the exhaust often. When checking the headers with a thermo cylinders 4,3,7, and 2 are cold and the others are like 150 degrees warmer. I have checked spark on all cylinders and compression (only on cylinders 1 and 2 at this point) changed distributors twice worked on Crank sensor signal checked pinout several times, checked and repaired grounds, done the relearn, probably countless other things I'm forgetting. One question I do have would exhaust cause this as I only have enough of my old exhaust on the headers to allow the front O2 sensor to be present. I am going to try and post my tune here and a few log files of it running. If anyone can see something I'm not or knows what it could be that would be great. Also let me know if there is something I'm forgetting to tell you guys and gals. Thanks!
mytruck.hptanother quick run.hplrun 2 4500.hplred truck second run.hpl