Ranger
Well-Known Member
That tach started bouncing around..........again. As some may recall, this has happened before. Here is the history to this puzzle that I hope someone can help with.
First time was last spring, shortly after I bought it and drove it home (from Detroit). That time it turned out to be the orange & blue ECU going out from being over charged by a bad factory voltage regulator. Replaced the ECU and the VR with a Wells VR706 on Big Johns recommendation. Voltage runs a consistent 14-14.5v. Problem solved. Reference: If anyone is interested. http://www.69roadrunner.net/mopar/showthread.php?12266-Electronics-Gone-Wild-HELP!
Months later (last summer) it started again. No misfire involved so I suspected the Tach. Pulled and cleaned the tach ground wire and it held an accurate and steady RPM. Problem solved.
A few weeks ago at the Farmington Mopars At The Park show in Minn. it started again, but this time it had an associated misfire. That turned out to be a badly oxidized 47 yr old connector from the battery to the starter relay. Cleaned it up and it ran fine all the way home (375 miles). Problem solved.
Last night it started bouncing around again. Cleaned and moved the ground to no avail. Thought maybe the tach was bad. Put a tach/dwell meter on the coil and it acted the same way, bouncing erratically.
HELP! I'm running out of ideas. :brickwall:
Actually, I have one, but don't want to lead anyone. I want to see if anyone confirms my suspicions.
First time was last spring, shortly after I bought it and drove it home (from Detroit). That time it turned out to be the orange & blue ECU going out from being over charged by a bad factory voltage regulator. Replaced the ECU and the VR with a Wells VR706 on Big Johns recommendation. Voltage runs a consistent 14-14.5v. Problem solved. Reference: If anyone is interested. http://www.69roadrunner.net/mopar/showthread.php?12266-Electronics-Gone-Wild-HELP!
Months later (last summer) it started again. No misfire involved so I suspected the Tach. Pulled and cleaned the tach ground wire and it held an accurate and steady RPM. Problem solved.
A few weeks ago at the Farmington Mopars At The Park show in Minn. it started again, but this time it had an associated misfire. That turned out to be a badly oxidized 47 yr old connector from the battery to the starter relay. Cleaned it up and it ran fine all the way home (375 miles). Problem solved.
Last night it started bouncing around again. Cleaned and moved the ground to no avail. Thought maybe the tach was bad. Put a tach/dwell meter on the coil and it acted the same way, bouncing erratically.
HELP! I'm running out of ideas. :brickwall:
Actually, I have one, but don't want to lead anyone. I want to see if anyone confirms my suspicions.
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