Trying to diagnose a ignition problem that showed its ugly face last fall
jim larson said
Apr 15, 2024
Car stated to suddenly quit on its own. I could restart it and it would run for a few minuets. Then it got worse. To the point that it would start and as soon as the key return to run it then would quit. I then used a jumper wire from the battery to the coil when I wanted to run/drive the cat.
Now Trying to find/fix the problem. Installed a new ignition switch from Karl. Switch has 5 posts. Just was told that my electrical connects doesn’t need/have a female connector for the GND terminal as I have Factory Gauges. Most TC members insist my electrical connector needs a female connector to it and 7 wires leading to it. Well I have only 5 wires and 3 female connectors (a couple are double connectors). I may be blind; buts thats what I see. I dropped the dash to get a good view.
Most suggestions I have received center around the resister wire problems; but how do you check that? And what other checks should I do? No power at the ING terminal at back of switch with key in run position. No power to Coil + with key in run. Fuse panel and fuse show good to go. Help
Put your test light or volt meter on the backup light fuse, this fuse should be hot any time the key is in the run or start position, check to see if it drops out when the engine quits, also turn in the radio.
If the backup light fuse loose power when the engine quits but the radio plays, check the pink wire at the ignition switch for poor connection, if the connection is good the ignition switch is bad.
Enganeer said
Apr 16, 2024
Original wire harness? My 64 had an issue that where it just stone quit going down the road and then would power on again. It was very intermittent.
By pressing on the wiring harness connection point by the firewall, it could keep it running. The issue was at the junction block between the engine wire harness and interior wire harness and the connector pins no longer provided enough deflection resistance to keep good contacts between the two harnesses. I replaced the harness after examining the wiring as they were very stiff and never had the issue come back.
jim larson said
Apr 17, 2024
Thanks guys. The cars runs now for whatever reason. I am thinking thr bulkhead connection/fuse panel resistor wire. But jumper wire is staying in the engine bay for when necessary.
I found out that the TC members who were telling me there have to be 7 wires going to the ignition switch were wrong. And the 66 service manual which shows 7 wires is wrong. I have only 5 wires. I plan to sand/scuff the coil connection soom.
Jim, does the car have breaker points or a Pertronix ignition?
jim larson said
Apr 20, 2024
Points, I believe the underdash, engine, and front light wiring are original. I have run the car during the last 4 days. No problems have surface.
dashboard said
Apr 21, 2024
Are you driving with the jumper wire between the battery and the coil?
jim larson said
Apr 21, 2024
I was when it wouldn’t run, dying just after start. I think the problem is fixed temporally. Connection of resister wire at bulkhead.
Enganeer said
Apr 22, 2024
Double check the resistance of the wires on your harness. I had what appeared to be good wires on the outside but corrosion had traveled from the terminal end connection deep into the wires. aka the green puss.
jim larson said
Apr 23, 2024
Not sure how to do that. I have been researching the methods.
Car stated to suddenly quit on its own. I could restart it and it would run for a few minuets. Then it got worse. To the point that it would start and as soon as the key return to run it then would quit. I then used a jumper wire from the battery to the coil when I wanted to run/drive the cat.
Now Trying to find/fix the problem. Installed a new ignition switch from Karl. Switch has 5 posts. Just was told that my electrical connects doesn’t need/have a female connector for the GND terminal as I have Factory Gauges. Most TC members insist my electrical connector needs a female connector to it and 7 wires leading to it. Well I have only 5 wires and 3 female connectors (a couple are double connectors). I may be blind; buts thats what I see. I dropped the dash to get a good view.
Most suggestions I have received center around the resister wire problems; but how do you check that? And what other checks should I do? No power at the ING terminal at back of switch with key in run position. No power to Coil + with key in run. Fuse panel and fuse show good to go. Help
Put your test light or volt meter on the backup light fuse, this fuse should be hot any time the key is in the run or start position, check to see if it drops out when the engine quits, also turn in the radio.
If the backup light fuse loose power when the engine quits but the radio plays, check the pink wire at the ignition switch for poor connection, if the connection is good the ignition switch is bad.
By pressing on the wiring harness connection point by the firewall, it could keep it running. The issue was at the junction block between the engine wire harness and interior wire harness and the connector pins no longer provided enough deflection resistance to keep good contacts between the two harnesses. I replaced the harness after examining the wiring as they were very stiff and never had the issue come back.
Thanks guys. The cars runs now for whatever reason. I am thinking thr bulkhead connection/fuse panel resistor wire. But jumper wire is staying in the engine bay for when necessary.
I found out that the TC members who were telling me there have to be 7 wires going to the ignition switch were wrong. And the 66 service manual which shows 7 wires is wrong. I have only 5 wires. I plan to sand/scuff the coil connection soom.
Points, I believe the underdash, engine, and front light wiring are original. I have run the car during the last 4 days. No problems have surface.
I was when it wouldn’t run, dying just after start. I think the problem is fixed temporally. Connection of resister wire at bulkhead.
Not sure how to do that. I have been researching the methods.