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Low Voltage Instability/Misfire?

650 views 2 replies 2 participants last post by  WickedSnake00 
#1 ·
As you may know, the dumpsterfire runs but is very unstable and frequently completely misfires. Even idle is very erratic, AFR is all over the place, usually reading lean, often full lean as it stumbles and misfires. (Note: plugs are pretty black and soot covered, indicating rich.) I was going back through the datalog and noticed that the voltage was showing only 11V. I know funny things can happen at low voltage, but could this be a root cause, or is it still in the tune? From my experience in the OEM world, devices are usually targeted to be capable down to 9V, but that's not necessarily Ford's standard in the 90s/2000s.
 
#2 ·
No That would not cause you to run rich or lean at 11V. Did you check your harness on the regulator like I suggested in another thread? normally when your voltage is low around 11V your regulator is not kicking in you can excite it sometimes by revving it up to over 3K if you have a 140+AM ALT.
 
#3 ·
I checked all the connections, everything was snug. I went on a hunch and checked a crimp I had previously repaired on the alternator cable. Sure enough, the harness side pulled out, and the only thing holding it together was the heat shrink, so I'm confident that was the cause. I'll just need to pick up a new connector.
 
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