Is there a trouble port on an 88 Eddie Bauer 5L with tfi ignition? Haynes manual wireing schematic shows one but I have searched hard and not found it.

 

Under the hood near the driver's side cowl. Looks like this.

 

Thanks!!! You wouldn't believe how long I looked for that. Will now go thru the test and maybe find my problem. (No spark but a series of flashes from tfi module). Replaced the coil and wires, still no spark. Purchased a new tfi module, discovered I needed a special wrench and heatsink paste. Ordered same and am waiting delivery..... scheduled for 6/1. Will run test tomorrow and maybe find I didn't need the module. Thanks again.

 

Attempted to run diagnostic test. Jumper in, ignition on, "check engine" lite comes on and stays on. I guess that could be caused by a bad chip in the tfi module. Hopefully changing the module will cure all.

 

Are you actually seeing pulses of light from the TFI module on the distributor? If so not good, I'd suggest you not install another module until you find the real problem. And FYI.. this truck requires a grey module not a black one.

Disconnect the wiring harness from the EEC(PCM) and crank the motor, any spark now? If not the PIP module inside the distributor is dead. If there is spark the PCM is bad.

 

I followed the procedure outlined in the Haynes manual ..ie.. check for power at one side of the coil primary, ignition on, crank and check conditions at the other side of the coil primary. Got flashes at what appeared to be firing speed. Haynes says if flashes are there to check coil. Coil resistances appeared good but I replaced it anyway. Still no fire.
I'm an old points & condenser man and remember years ago playing with the dwell in a boat Olds v8 ....... dwell made quite a difference in max RPM but too little or too much dwell caused misses. The flashes I read seemed mostly + and extremely short -. Could be just the way the LED made it look but I can't help but wonder.
We will see what the new TFi module does and go from there.

 

Got the parts (wrench & paste) and installed the new Tfi module. Started right up. It should be noted that on this 88 Bronco with AC you cannot rotate the distributor enough (large bracket for AC comp $ alternator in the way) to remove the Tfi bolts. Had to pull the distributor.