I have had a few TFI's go bad on me in the past...
I ran a Performance Distributors Screamin Demon ignition kit (bought it in '98 and ran it for about 2 yrs.) It came with a coil, brass term. cap and rotor, cool plug wires, and the infamous TFI module... It was alright for some time, but one day my car would turn over and not fire. I checked it all over, got spark at the coil but not at the plug, etc. Finally after reading, checking, and process of elimination, I discovered it was that damned TFI module. They covered the first one, but soon after I had to replace it again and was so frustrated that I replaced it with a Wells stock/factory TFI. Couldn't tell any difference in power...
And I recall a few times where my car had stalled at various places, waited around awhile (sometimes longer than others), scratch my head, check connections, etc., and FIRE! rumpity-rump away I go!
TFI modules are FUN... I look forward to replacing one in the future... Make sure when you replace your TFI that you use the silicone di-electric compound on the backside.
I don't believe I have ever encountered an erratic ignition/misfire because of a TFI, usually the car doesn't get ANY fire...
(in my experience anyhow)
Take care... and good luck
