Canon Lansdell
OBS Enthusiast
Hello all. I have a severe misfire on my 98 K1500 that started randomly while driving weeks ago. Misfired on almost every cylinder intermittently, but most on cylinder 6. First thing i changed was spider unit to MPFI setup. Read 55 psi (should read 60-65) fuel pressure. Next changed fuel filter prematurely, ran like a top until I got up to 95 mph where the misfire came back. Tested charging system to make sure everything was getting power, yes it was fine. Cleaned fuel strainer and it ran better but it still had a miss. Next changed fuel pump, misfire persists. Any one experienced this? Also, newer distributor, spark plugs, cap, wires. Tested ignition coil and ICM voltage and it was good. Any ideas?