random miss / steady miss
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random miss / steady miss I have an 06 6.0 in a 72 chevy p,u. Frame is from an 05 envoy. New wiring harness ,with new msd 6014 - holly manifold - 750 edelbrock, compression on all cylinders 165 to 170. System has multiple grounds. Operating voltage is 13.4 v.
When we first started the motor, we han a ramdom miss. Installed new correct plugs. Miss stabilized on cylinder # 7.
Called msd. They had us had me switch coils around, switch plug wires around, move left coil power wires left to right. Remove wiring harness & check coninuity, all ok. While removed checked for proper wire placement - all correct. Used timing light to assure all coil wires were firing, set motor @ 1500 rpm, unplugged coils one at a time - # 7 showed no difference.
What am i missing?????
When we first started the motor, we han a ramdom miss. Installed new correct plugs. Miss stabilized on cylinder # 7.
Called msd. They had us had me switch coils around, switch plug wires around, move left coil power wires left to right. Remove wiring harness & check coninuity, all ok. While removed checked for proper wire placement - all correct. Used timing light to assure all coil wires were firing, set motor @ 1500 rpm, unplugged coils one at a time - # 7 showed no difference.
What am i missing?????
Sounds like you’ve covered the basics as far as spark and compression. I don’t think a leak down test would be much benefit here. And the carb more or less takes care of fuel and air and this seems to be isolated to one cylinder.
If it were me my next step would be looking at the valve train on #7 cylinder. Check for a bent push rod or collapsed lifter in the form of a lazy valve rocker. You may need to check with a dial indicator but the bad ones can be seen with the naked eye.
If it were me my next step would be looking at the valve train on #7 cylinder. Check for a bent push rod or collapsed lifter in the form of a lazy valve rocker. You may need to check with a dial indicator but the bad ones can be seen with the naked eye.
Welcome to the site. You might also try starting another thread in the Hybrids & Conversions section where there's a chance you might find a collection of folks who have gone through a similar experience.
