Lots of posts on this topic but I couldn't find one that answered my specific question. I went to the GM/Delco parts site to try an determine the correct ICM module for my 85 V6 SE. My original ICM finally bit the dust after many years and after replacing the entire distributor with a new one, the ICM quit after only a few hundred miles. I'm convince its a heat-related issue due to other vendors now building these parts.
After entering my full (VIN 1G2PF3796FP266811) the Delco site came back with 1985 Pontiac Fiero 2.8L 173 cid V6 VIN:9
The ICM shown were:
Ignition Control Module Part Number: D1943A Product Notes: Ignition Control Module All; w/o HEI; VIN: 9* Per Vehicle: 1; Years: 1985-1985
Part Number: D1984A Product Notes: Ignition Control Module Per Vehicle: 1; Years: 1985-1988
Part Number: D1906C Product Notes: Ignition Control Module Per Vehicle: 1; Years: 1985-1988
So basically 3 versions without any specifics as to the differences and one version specific to the 1985 year. So the D1943A would be correct and likely the one that came with the vehicle from the factory, but the other 2 could also be compatible. Also, the VIN: 9 must be significant since there is a specific ICM that references it.
I'm in the electronics business so I fully understand the importance of heat dissipation and what can happen when components are exposed to high heat with no where for that heat to go. Products sourced in China by US companies should be tested by those companies to meet the OEM specs so habitual failures would be the fault of the US concern not where they are made.
At this I was looking for feedback on which specific Delco versions other members have used. with success.
Heat Is Not the only or even the worse problem(s) that can kill an ICM. F'ed coils (main and pickup), cap/rotor, plugs and plug wires, etc, can repeatedly fry the ICM. See my Cave, HE Ignition
------------------ Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should. (Jurassic Park)
With or without an additional heatsink, decent thermal compound between the ICM and the distributor base will certainly help to keep the ICM cool. Good to see that there's a quality thermal compound readily available from a common retailer. (Common in the States anyway as Radio Shack has disappeared from Canada.)
I can't open that link, but I assume from the "Silicone Valley" reference that it is intended for computers.
When I went to a computer store looking for something for my ICM, the guy was adamant that the heat sink for computers will not withstand the heat and humidity from automobile use.
RS HS Grease is nothing but standard White HS grease sold everywhere for 40+ years. Is just Silicone oil w/ Zinc Oxide.
Can get that and other types thru Digikey, Grainger, Mouser, Amazon, etc. etc. etc. Often w/ larger package for less money per ml.
Some use same Hype grease sold to fools in the PC market to try to get CPU 1 or 2 degrees cooler. While most works as HS grease is mainly hype to sell at High $. Like Many think Silver color mean Silver metal but most are just Aluminum. Warning: Do Not use Gallium etc. "Liquid Metal" HS goo or you will ruin the distributor at minimum and often in hours. Most of YT videos showing Gallium and others eats Aluminum are real. Most "Liquid Metal" goo has same warnings Not to use them w/ Aluminum HS etc.
I hate the small packs but Most people Should Not get a large tube/bottle of any HS grease. Silicone Oil and other carriers can separate in the pack, More so if stored in hot places and DIY mixing won't help trying to fix this problem. DIY mixing can't delver uniform mixing of oil and zinc etc. Worse, Non-silicone HS Greases may have part of the grease that evaporate out of the package after opening. Either problem meaning the grease is too thick to flow right and doesn't perform or worse if used months to years later.
If you have Permatex Brake Grease... Can use it in place of HS grease. Does flow under pressure but won't run and never dries out and won't hurt plastic/rubber. It flows so thin the metal parts actually touch everywhere they can to transfer heat directly. But is a real grease and will move until you install the screws etc.
Note: DIS modules are installed Dry from the GM factories. Anyone Adding HS grease other makes problems because the module is so big and grease can't flow making uneven pressures in the module. I install them w/ Brake Grease or Silicon Oil. Is to seal the faces to prevent corrosion as well as transfer heat a little better. Why? Unlike some others, 87+ Duke DIS module is very low on the engine and easier to get spayed w/ road trash and polluted water. Any Corrosion block heat transfer, if bad enough can put uneven pressure on the module too.
