Ignition Control Module?

It's probably either the TFI module or the PIP sensor, but it doesn't matter which one of the two is at fault 'cause you'll need to replace the whole distributor anyway. I do suggest that you convert the TFI module to remote mount on the passenger side inner fender (SN95 style) to reduce the risk of future failure, so consider buying this kit:

McCully Racing Motors- We have exactly what your over-heated TFI Module Needs!

Does the radio, heater or blinker go crazy when it shuts off? If so the ignition switch is bad.

Yes, there was a recall on Fox 5.0's regarding the high failure rate of their distributor-mounted TFI modules due to heat soaking. That's why you need to remote mount it in a cooler place.

MikeUrban said:

nope, everything just shuts off. Also, I think alldata said something about a recall for 88-93s and their ICM. Does anyone know if there was one?

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If everything shuts off- engine, radio, wipers, A/C blower, then it is definitely the ignition switch.

There was a FREE recall on Ford ignition switches. Since this is very old information, you may not be able to get the switch replaced for free anymore. The ignition switches overheat and sometimes catch fire. That burns up the steering column and sometimes the car interior. The auto parts stores sell the switches for $13-$15.



Saleen0679 was nice enough to dig this up for us awhile back: Replace a 1979-1993 Ignition Switch Assembly

My car doesnt start when I turn the key, but will start when I jump the relay with a screwdriver. This problem started after i drove in heavy rain. Could a bad ignition control module be the cause? Is there any way to test the ignition control module?

sully88gt said:

My car doesnt start when I turn the key, but will start when I jump the relay with a screwdriver. This problem started after i drove in heavy rain. Could a bad ignition control module be the cause? Is there any way to test the ignition control module?

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Welcome to the boards!

You'll want to start your own thread.

It's the not ig module. There's likely an issue with the interlock wiring or the solenoid itself. Jrichker will be able to provide a diagram and diagnostic to get you up and running.

Look closely at the ignition switch wiring. Look for loose wires, wires showing evidence of overheating, melting of the wiring and melting of the plastic wiring connector shell. Look for wires that are not securely fixed in the plastic wiring connector shell.

Have you done the wiggle / thump test? Get the car warm, park it in neutral, pop the hood, and start wiggling harnesses / connections and tapping on things (the ECM comes to mind). I've found many an intermittent electrical problem like that.

My car kept shutting off randomly and wouldn't start for a little bit and it turned out to be the PIP sensor. Try that and see what happens.

MikeUrban said:

Yes, I tried that yesterday. I wiggled every wire and plug, tapped the TFI, jostled the battery, shook the MAF to TB hose. Nothing made it misfire. About 5 min of idling after that it shut off and then when I tried to start it and it fired right up as if nothing happened. I'm honestly thinking about doing an EFI to Carb swap now, but I don't think I'll pass emissions if I do.

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You definitely won't pass the visual inspection for emissions if you do an EFI to carb swap.

Try dumping the codes. The computer monitors all the circuits and can often tell you what shut off when it wasn't supposed to.


Dumping the computer diagnostic codes on 86-95 Mustangs

Revised 19-May-2009 to update drawing for dumping the codes on 86-88 Mustangs with no check engine light.

Dump the codes and see what the computer says is wrong…Codes may be present in the computer even if the Check Engine light isn’t on.

Here's the way to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

Be sure to turn off the A/C, and put the transmission in neutral when dumping the codes. Fail to do this and you will generate a code 67 and not be able to dump the Engine Running codes.

Dumping the Engine Running codes: The procedure is the same, you start the engine with the test jumper in place. Be sure the A/C is off and the transmission is in neutral. You'll get an 11, then a 4 and the engine will speed up to do the EGR test. After the engine speed decreases back to idle, it will dump the engine running codes.

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

See Troublcodes.net Trouble Codes OBD & OBD2 Trouble Codes and Technical info & Tool Store. By BAT Auto Technical





If your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.



The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.

89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.



The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.


WARNING!!! There is a single dark brown connector with a black/orange wire. It is the 12 volt power to the under the hood light. Do not jumper it to the computer test connector. If you do, you will damage the computer.

What to expect:
You should get a code 11 (two single flashes in succession). This says that the computer's internal workings are OK, and that the wiring to put the computer into diagnostic mode is good. No code 11 and you have some wiring problems.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

Alternate methods:
For those who are intimidated by all the wires & connections, see Actron® for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

Or for a nicer scanner see Equus - Digital Ford Code Reader (3145) – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $30.

Dumping the codes works as long as the computer and wiring are good. If the codes won't dump using a jumper, repost and I will try to help with the Computer won't go into diagnostic mode tech note.