A buddy of mine has a 1986 F-150 (speed density FI) and it has now blown 4 or 5 TFI modules. I have never seen more than one (the occassional going bad type) blow. Anyone out there have any experience with this? His tach doesn't work, not sure if maybe that is drawing amperage somewhere or what. I can't find my spare distributor, but he did buy a new one to try himself.
The only things I could think of that might do it would be a current draw or a short.
Ignition switch?
Voltage too high? Check the battery voltage with the engine running, rev it up. If the V/R is working it should not go above 14 to 14.5 volts.
Too hot? Are you putting the white goop on the TFI?
Never saw an ignition switch do that before. Yes I made sure he was putting di-electric grease on before it goes on the distributor.
Is he using Motorcraft? If he is getting them from autozone that is probably why brands like wells are .
Other than that what I have heard is changing the PIP and coil along with the TFI all at once with good brand stuff will cure it.
Changed the coil??? The module current draw is through it...
Yeah, I wonder if it has a non stock coil that draws more current than stock.
Is he sure it is the white grease (thermal conducting) and not di-electric grease. They are not the same.