AMC 304 ignition box testing

[93mustang]

Hi! New to site here and have a question. Can anyone tell me how to test an ignition box? I have a 76 model AMC 304 with the electronic ignition. Installed a NAPA electronic distributor and ignition mmoduleback in August. I am getting an intermittent fire and sometimes none at all. I have tested the coil and it is good. Can't figure the intermittent fire though and would like to test the amplifier. Thanks in advance!

[jeepsr4ever]

Usually they just go out. Hmm do you have any splices in your wiring like on the purple wire from the box to the dizzy? Reman'ed dizzy?

[93mustang]

No splices. The dizzy is a reman. I was also thinking it might be the pick-up in it? Is that what you were eluding too? If so, how would I test for that?

[jeepsr4ever]

I have was having the same issue with 3 of those last fall...not sure was probly the pickup malfunction.

[93mustang]

Okay. Thanks. Did you finally get a good one from them or have to go somewhere else?

[jeepsr4ever]

No after that I never bought from them again. I used a dizzy we had in a wagoneer.

[tufcj]

In 76-77 they used the Prestolite ignition, in 78 they went to Motorcraft. I had it in my 77 also. Left me stranded at least twice before I junked it and installed the Mallory Unilite.

One thing is ground. The ECU box on the fender MUST have a good ground. Without ground, no spark. Mine quit once when the ground wire broke.

I wouldn't waste a lot of time on the Prestolite, it's junk, that's why AMC quit using it. For what you'll spend for rebuilt parts, you could have a quality aftermarket distributor, and less headaches. You could even convert to Motorcraft by pulling the distributor, ECU, and wiring from a Wagoneer, and splicing it into your system (just 3 or 4 wires).

Bob
tufcj