No spark while cranking?

[Gerald Morris]

I think you want to leave that in place so it powers the ECU, but I could be wrong.

The car is a '72, and the electronic ignition was a factory option that year, so I assume it's been rewired like the factory did. There's a screwy "back feed" (for want of a better term) that comes back through the ballast resistor to limit current and power the ECU.

I think it's safe to assume the coil and ECU is OK as the car will occasionally fire as the key is let off.

I'm thinking the fault is in the ignition switch, bulkhead connector or wiring. Since it's been rewired, that also brings in the quality of wire and connectors/crimps.

I suspect you're right. Yes, in retrospect she needs to feed current to the ECU from something, and that might be the only junction.

I had a merry time with getting a 4 wire ECU to work on my D150. It's ALMOST a "plug and play" setup, but I had to make a little bypass to the ignition using a NO relay with the starter loop. With that, the ignition gets full current when starting, and then the usual fraction once started. The fact that the starter relay on the '83 had contact points, but no actual circuiting for such suggests the processor board did that bit of switching. I still have it, as somebody might want to rebuild one.

 

[1970FuryConv]

Hi all,
I bring up this old thread because I have the same issue and did not find a solution yet. My 72 Newport with factory electronic ignition does not produce a spark while cranking, but it does, when the ignition switch is in Run position.

I changed the coil, the pick up, the ballast resistor and the ignition box, but nothing changed. I measured all wires if there is the voltage that should be there, coil gehts about 8v in run and full 12v during start. Also checked IGN1 and IGN2 wiring, all fine and provides the voltage it should. Also measured the pins of the ignition box, has voltage where it should and resistance where it should.

Read about bad ground to the block, so removed the ground cable, cleaned everything, reassembled all parts, still no spark during cranking.

I am running out of ideas. The engine sometimes fires up, when I release the ignition switch from start and it goes to run position. Apparently sometimes there is enough momentum left from the starter so the engine still turns when the spark from Run position appears and then the engine runs normally.

Any ideas what else I could check?

Thank you so much.
Marian

My 1973 Monaco had the same problems.
Replacing the ECU fixed it.
@halifaxhops sells quality ECUs. The ignition box you bought may be junk.
Best of Luck.

 

[halifaxhops]

I have them also a book that stupid's down the system that you can trouble shoot with a meter. PM me if you need it. Need a few days though have to unload from Carlisle.

 

[Big_John]

I have them also a book that stupid's down the system that you can trouble shoot with a meter. PM me if you need it. Need a few days though have to unload from Carlisle.

I have that same book and IMHO, it's something everyone with Chrysler electronic ignition should have.

 

[schwarzsurfer]

Hi,

seems like a combination of a broken pick up and a worn out distributor rotor + cap caused the problem. After replacing these parts the engine starts right up!

Thanks for your support!
Marian

 

[73 grancoupe]

That's interesting.