So i was driving to the shop yesterday and everything was going fine. Stopped at a red light and 100 ft after the light the car started stumbling and eventually died. So it started back and went a little further and died, couldnt get it started back so we towed it to the shop. It sat in the shop for awhile and then we started it back up no problem and idled fine. Replaced the fuel pump and it started perfect and idled fine. Took it for a short spin and no problems. Leave the shop to head home and it starts cuting out/losing power when I press the gas pedal. Recently I have replaced the fuel pump, fuel filter, spark plug wires, regapped the plugs all within the last two weeks. Any suggestions for what the problem is???
the ignition module may be over heating. thats how an overheating igniton module behaves. the modules are cheap. i would just try replacing it. they are dificult to test.
It could also be a coil breaking down. They heat up and fail - just as you describe and then when they cool off they work fine until they heat back up again.
goto store and order a hei module for a chevy. try 85 c1500 with a 350 if they need a vehical or goto the performance section and accel should have a performance hei module. take it home. now take off your distributor cap. look in the base of the distributor. you will see the module, its the same shape as the one you bought. there should be two screws and two plugs to undo. then reverse the order for reasembly. you should be able to do this in the auto parts store parking lot if you really want to. that will confuse the store employes. a ford geting a gm hei module in a hei on the front of a motor. 10 to 15 years ago i wouldnt have belived it
It could also be moisture under the cap. If you don't find any moisture and nothing looks corroded under there, do what Bryant says. You'll know you probably have the correct HEI module if it has four pins. When you reassemble, put some dielectric grease between the module and the body of the distributor. Ignition modules need a heatsink. That's why the Duraspark has that big metal box. The HEI uses the distributor body itself as the heatsink.
I've read this before, and it makes the HEI sound like a time bomb. It makes sense unless you consider how many of these things were and are still running reliably with practically no maintenance. The '74+ design is really quite solid. A lot of the things brought up in that article are just not issues in the real world, although they certainly sound like they should be. You would think, with the already hotter than stock coil I'm running, plus the MSD box, my distributor would be constantly misfiring, eating up contacts under the cap and spreading carbon dust everywhere and that's just not what's happening. I had to replace my cap once because of an unrelated fire. When I did, the rotor button and the inside of the cap still looked new after three years of daily driving. I can't speak for the longevity of the HEI module in this car because I long ago replaced that with an MSD box, but I've had no trouble out of them in other daily driven cars. Maybe the early ones were failure prone, or certain cheap aftermarket ones? I don't know where that comes from, they just don't fail that much. ...I am not trying to say that the HEI is better than the Duraspark. In practice I just don't think there's enough difference between the two that it matters. Neither GM nor Ford were famous for ignition failures back then as far as I know, so unless you're just eaten up with all that "Chevy is junk, bleed Ford blue" mentality, it doesn't matter either way. I went with HEI for the sole reason that I needed a new distributor, my Duraspark stuff was practically falling apart, and over a decade of Chevy bigotry had made me extremely familiar with it. It solved my problem when I installed it and it hasn't let me down yet, so why change it?
