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TFI Ignition Module

1987 Ford F150 302, 5.0L

I’ve been reading about the problems associated with Ford TFI ignition modules in mid 80s to mid 90s vehicles. I recently pulled out the distributor to change the pickup coil and decided to put a couple layers of heat resistant tape on the outside of the module. The stock one eas replaced by a mechanic a few months ago because it died and wouldn’t start. Anyone else used anti heat tape to protect the module? What other means has anyone used to keep it from getting overheating and failing?

I would suggest you remove the tape to keep the unit cool. The heat comes from within and wants to get out.

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I remember having a 1989 Ford Tempo with this issue.I went through 3 ignition module with this car because Ford engineers decided to install the module at the base of the distributor.The car would quit working after a while because these modules were heat sensitive.I don’t think anti-heat tape would cool the module but cook it instead. I think Ford put some dielectric grease at the base of the module but that wasn’t enough I guess.

Don’t use tape

I believe it’s supposed to be a paste or grease

Either the clear dielectric grease, as @COROLLAGUY1 mentioned, or the white paste, which I’ve seen used to keep blower control modules/resistors from burning up

The advice I gave was not Ford-specific, but more general in nature

I did use dielectric grease as directed on the flat part contacting the distributor, but put the tape on the outside casing of the module. I’ve literally just out it on and driven it maybe 4 miles. I just hoped to keep it from stalling on the road

Again, the tape will make things worse, as it keeps the heat in the module instead of letting it dissipate.

What you want is a silicone base heat sink compound and spread it generously on the metal underside after cleaning the old stuff off then tighten it down. I have seen the 302 plenum bolts behind the distributor have thick plastic caps and wonder if these are a heat shield of sorts. The thermostat is nearby also so make sure your temps are good. That ignition module should last a good long time but carry a spare for that day it dies in the middle of nowhere.

Try the tape idea. If it solves the problem, done. If not, you could try gluing heat sink devices to the outside of the distributor. Even if all you did was glue a small L-shaped piece of sheet metal to the distributor casing or dist cap, it would probably do some good moving heat away. Even better if you can find a big heat sink from an discarded computer. For glue my first thought is JB Weld Original, b/c it has bits of metal in it, so it should conduct heat better than plain epoxy. There are special purpose heat conductive epoxy’s available too. Make sure to keep the dist and dist cap clean too, b/c dust will act as an insulator holding in the heat.

I’ve seen a similar technique done on wood burning stoves chimney pipes, to extract a little more heat before it goes out the top.