TFI Module Testing?

PRO5OHHO · Mar 18, 2014

I've found a ton of diagrams on the internet for testing the fox body (distributor mounted) TFI modules but none for our year cars. The foxes have pins on the side & @ the main connector for testing resistance but ours don't. They only have pins @ the connector. Anyone run across a diagram like that? I've got a crank/no start condition on the car (just died while coasting, and hasn't started back up after days of sitting), I have fuel & spark, and the rotor spins, so that leaves:

a) TFI module
b) Pickup coil
c) ignition module
d) engine ground
e) loose wire in the connector underneath the coil
f) PCM
g) ICRM

I figured the TFI & the engine grounds would be the easiest to check first.

toyman · Mar 18, 2014

If I were to guess the most likely cause is the PIP (Hall Effect Sensor) in the distributor. As a caution, reman dizzy's are prone to PIP failures. Your best bet is an all new Richporter dizzy for about $100.

2slo95fiveoh · Mar 18, 2014

I could be mistaken, but I thought I had seen a few people say they had their TFI module tested at Autozone?
This could be something made up in my head, so take it with a grain of salt, but I could have sworn I've heard others saying that.
The PIP has a very large failure rate, so I would put that at the top of the list for possible causes too.

CC'S95GT · Mar 19, 2014

You can test the pip just by turning the rotor.
Mark the rotor then pull the dizzy out enough to freespin the rotor. Turn the ignition on /engine off, then after initial 3 second time out of the fuel pump spin the rotor on the dizzy. If you hear the FP come back on then the pip is working.
The problem with the PIP is the failure is heat related in the begining and gets worse over time. So the test might not be accurate when the engine is cold.
Restab the dizzy with the rotor pointing to the mark you made in the begining.