80 Ignition problem
Thread Starter
Intermediate
Joined: Dec 2016
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80 Ignition problem
I have an 80 California car ( It has a ECM ) I seem to be having an Ignition problem. I changed out the coil and it went away for awhile but now it's back. I then changed out the electronic module in the HEI and again it went away... After I drove for a few days I was out on the town and when I started it to leave it stated to act up again. It wont Idle you have to keep your foot on the gas to keep it running and it seems to be missing like crazy. It has an ECM but its not the stock motor carb. or HEI. Could the ECM be doing something like shorting the Hot to the HEI? It seems to only happen once the car gets wormed up.
Le Mans Master
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I have an 80 California car ( It has a ECM ) I seem to be having an Ignition problem. I changed out the coil and it went away for awhile but now it's back. I then changed out the electronic module in the HEI and again it went away... After I drove for a few days I was out on the town and when I started it to leave it stated to act up again. It wont Idle you have to keep your foot on the gas to keep it running and it seems to be missing like crazy. It has an ECM but its not the stock motor carb. or HEI. Could the ECM be doing something like shorting the Hot to the HEI? It seems to only happen once the car gets wormed up.
Thread Starter
Intermediate
Joined: Dec 2016
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Le Mans Master
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From: Cool Northern Michigan
Just the thought of a 305 in a C3 turns my stomach. I find that hard to believe but maybe.
One item that just hates the heat inside that dizzy is the modge. You said you changed it. Did you apply Heat Sink Compound to the bottom of the modge? If not, you are back to square one. Do not use dielectric grease. Completely different material.
One item that just hates the heat inside that dizzy is the modge. You said you changed it. Did you apply Heat Sink Compound to the bottom of the modge? If not, you are back to square one. Do not use dielectric grease. Completely different material.
Last edited by HeadsU.P.; Apr 8, 2018 at 01:09 PM.
Thread Starter
Intermediate
Joined: Dec 2016
Posts: 39
Likes: 2
Just the thought of a 305 in a C3 turns my stomach. I find that hard to believe but maybe.
One item that just hates the heat inside that dizzy is the modge. You said you changed it. Did you apply Heat Sink Compound to the bottom of the modge? If not, you are back to square one. Do not use dielectric grease. Completely different material.
One item that just hates the heat inside that dizzy is the modge. You said you changed it. Did you apply Heat Sink Compound to the bottom of the modge? If not, you are back to square one. Do not use dielectric grease. Completely different material.
Good call. I changed it with one from a spare HEI on my parts shelf. I didn't add any more grease. My new PertronixIII Module just came in so I will replace it with plenty of heat sink grease and let you know.
Last edited by Ohsoez; Apr 10, 2018 at 12:54 PM.
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Thread Starter
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Ok now I'm confused... I changed the module and now it runs bad from the start. Before the motor would have to heat up now it starts hard and wont idle. Could the computer be the problem? Is there any way to bypass it?
Le Mans Master
Joined: Aug 2017
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From: Cool Northern Michigan
Just to make us feel better, take the dust cover off the dizzy cap. Should be three screws. Take a peek around under there especially where the 12V comes in the side of the cap. All wires, connections look good? Should be a black ground wire on one corner of the coil. Remove that hold-down screw and wire brush the paint off the coil corner and wire terminal end. Re-install. You have to have a good ground there.
(IDK about ECM)
(IDK about ECM)
Le Mans Master
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Unplug the carb or the dizzy. If you get a check engine light, its bypassed.
Thread Starter
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Just to make us feel better, take the dust cover off the dizzy cap. Should be three screws. Take a peek around under there especially where the 12V comes in the side of the cap. All wires, connections look good? Should be a black ground wire on one corner of the coil. Remove that hold-down screw and wire brush the paint off the coil corner and wire terminal end. Re-install. You have to have a good ground there.
(IDK about ECM)
(IDK about ECM)
Le Mans Master
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So, the ECM is not hooked up to anything but a source?Basically, the ECM is irrelevant. Lets leave that off the table.
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Race Director
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No cracks in the cap or rotor?
how old are the plug wires and can you check their resistance with an ohm meter, 1K/foot of wire?
Only three parts to HEI, ignition coil, module, pickup coil, what havent you replaced?
how old are the plug wires and can you check their resistance with an ohm meter, 1K/foot of wire?
Only three parts to HEI, ignition coil, module, pickup coil, what havent you replaced?
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Plug wires only a yr or two old I've swapped out the coil, cap, rotor, with spares I had in stock and a new module. It used to miss after it warmed up but after I changed the module it started rough and wont Idle.
Le Mans Master
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Verify the white wire from the pick up goes to the module "W."
The pick up "could" be failing on a cheap dizzy.