Ok guys need some mopar help !!
I caught a random start two times past few days but havent been able to again.
Just bought a 72 challenger from a 19 year old whos grandfather passed as he needed money for college. He couldn’t figure out how one day it starts and the next few days it doesnt and so on bit was otherwise a stellar restored car. It has had intermittent starting issues since he got it. He replaced new coil, wires, plugs, starter relay, and neutral safety switch but still no success. The challenger has a 360 LA block with msd conversion that was all checked for proper wiring as well.
my problem is im not getting spark while crabking but have 12v to msd box
Here is what i have done to diagnose.
1. I checked the battery to block ground at
0 ohms.
2. I checked the firewall to block ground at
0 ohms
3. I have 12v of switch power and cranking power to the MSD 6a
4. I did the jumper test per MSD of the green and purple distributor trigger wire connection from the MSD 6a to coil, took coil wire distributor side off and grounded it to block then took screw driver and jumped the starter relay with key in on position with screwdriver and watched excellent spark popping off.
5.checked with test light IGN1 brown which was from positive coil under column and on bothside of bulk head
6. Checked blue/white-trace with test light on both sides of bulkhead
7.checked connection of 12v little red feed wire and its receiving the power from ign1 and ign 2
8. yellow cranking wire from ignition switch test lights up while cranking.
So what the hell is going on here i have complete spark down to spark plugs doing the trouble shoot jumping the magnetic Trigger wires with key on but cranking i have nothing dead as a door nail?
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