Help! Car keeps dying

[sadil340]

New member here, so apologies if I missed any previous threads. My car (1970 Cuda 340 4-speed) has been converted to electronic ignition. Lately it dies unexpectedly and I've yet to find the problem. I've replaced the ECU, the ballast resistor, the coil (Accel) and the distributor. I suspected that I caused it by tapping the bulkhead blue wire for my electric choke but disconnecting that lead doesn't solve the problem. I've multitested the coil and ballast resistor (.8 ohm MSD model) and it checks out - when it's running.

Thanks for any suggestions!

 

[Mopar Nut]

 

[340challconvert]

to FEBO from New Jersey.
Good people here who can give you some insight into your problem!

 

[sir_veza]

New member here, so apologies if I missed any previous threads. My car (1970 Cuda 340 4-speed) has been converted to electronic ignition. Lately it dies unexpectedly and I've yet to find the problem. I've replaced the ECU, the ballast resistor, the coil (Accel) and the distributor. I suspected that I caused it by tapping the bulkhead blue wire for my electric choke but disconnecting that lead doesn't solve the problem. I've multitested the coil and ballast resistor (.8 ohm MSD model) and it checks out - when it's running.

Thanks for any suggestions!

Welcome to the Forum. Does your car have an MSD ignition box? If so check the ground wire is nicely grounded. As well as the engine ground is a strong strap style to the firewall.

 

[Challenger RTA]

As mentioned above check the ground. And if it still dies. Run a wire from under the steering column plug blue run wire to the ballast resistor. No need to disconnect the original wiring. It's a test to see where the problem is.
You can also run a wire from the battery+ to the resistor blue side. The motor will keep running until you disconnect it.

 

[sadil340]

Welcome to the Forum. Does your car have an MSD ignition box? If so check the ground wire is nicely grounded. As well as the engine ground is a strong strap style to the firewall.

It’s currently using an old Rev-Nator ECU. I switched it for a new orange box with no change. I made sure it was well grounded.

 

[sadil340]

As mentioned above check the ground. And if it still dies. Run a wire from under the steering column plug blue run wire to the ballast resistor. No need to disconnect the original wiring. It's a test to see where the problem is.
You can also run a wire from the battery+ to the resistor blue side. I motor will keep running until you disconnect it.
View attachment 131154

Interesting suggestion, I’ll try that.

 

[Daves69]

Maybe review the conversion instruction and troubleshooting.....

Mopar Performance Electronic Ignition Kit Instructions

 

[6PKRTSE]

Check the main bulkhead plug at the firewall connector.

 

[fasjac]

Welcome to the site from Arkansas.
Ditto on the AP

 

[Xcudame]

Welcome to FEBO from the desert! Post some pictures of your 70 340 Cuda!

 

[sadil340]

New member here, so apologies if I missed any previous threads. My car (1970 Cuda 340 4-speed) has been converted to electronic ignition. Lately it dies unexpectedly and I've yet to find the problem. I've replaced the ECU, the ballast resistor, the coil (Accel) and the distributor. I suspected that I caused it by tapping the bulkhead blue wire for my electric choke but disconnecting that lead doesn't solve the problem. I've multitested the coil and ballast resistor (.8 ohm MSD model) and it checks out - when it's running.

Thanks for any suggestions!

Turns out the cause was pretty simple: the main coil wire lead had been pinched by the old coil which had a smaller opening. The new Accel coil was larger, so the lead wire eventually vibrated its way out. I wish they were all that simple! Thanks for all of the suggestions; there's some great information here.