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GM HEI

This is a followup to a post I made yeasterday, which was that I was unable to correct a miss for a 350 which has new plugs (.045), wires, cap rotor, carb and a host of other non ignition related upgrades. Anyways I replaced the 2 month old plugs with new Bosch Platinums tonight, and replaced the wires again. two plugs looked to be oil fouled with lots of deposits. So when I get everything in and set, it runs great in the 2000+ rpm range, but wont idle barely at all. It has a horrible miss on multiple cylinders, but it all smooths out at higher RPM. Am I correct that this sounds like a coil, or is there something that i might Have ovverlooked somehow. The engine has 140xxx miles on it, and runs strong yet.

Thanks in advance Zach

Reply to
Zachary Sandberg
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check your firing order. 1-8-4-3-6-5-7-2

nate

Reply to
Nate Nagel

while I havnt checked the firing order the engine runs extremely smooth above 2k rpm. Keep in mind this is a problem that just all of a sudden started after i was already drving down the road for 2+ hours. I will check the firing order this morning, but unless wires switch themselves around on the fly, I dont think this will be the answer.

thanks, Zack

Reply to
Zachary Sandberg

Why assume automatically that it's an ignition problem? You said you had two badly fouled plugs from oil. That sounds more like a cylinder problem. Check those plugs again if you remember which cylinders. Otherwise pull all plugs and inspect.

Reply to
Al Bundy

I'd check for a vacuum leak next.

Reply to
NickySantoro

I made a sort of foolish post some months ago about the HEI system (not my first error, and probably wont be my last either). The earlier GM HEI systems had the coil built into the distributor cap, as I remember it. Later versions were, I am told, different.

If yours is of this earlier type, you need to be aware that internal arcing around the coil and even inside the cap itself is something you need to keep in mind.

Reply to
<HLS

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