My son's full size 89 with 5.0 has an intermittent issue. After getting to full operating temp and reaching destination, when he gets back in vehicle it will start, run a few minutes then stall. Starts most every time though occasionally it won't start. He waits a few minutes and then it starts.....sometimes stalling again.......sometimes he takes off and all is goodHe can go for days or even weeks with no issue then it appears again. Intermittent issue.
Intermittent no start when at max operating temp
- Thread starter Greg B
- Start date
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Ignition module would be first guess, second guess would be fuel pump.
Need to check for spark during a no start situation. That would point you in the right direction.
harbor freight has these handy inline testers. You install it on a plug wire or coil wire and leave it. When the no start occurs, pop the hood and see if it is flashing while cranking.
https://www.harborfreight.com/in-line-spark-checker-63590.html
Need to check for spark during a no start situation. That would point you in the right direction.
harbor freight has these handy inline testers. You install it on a plug wire or coil wire and leave it. When the no start occurs, pop the hood and see if it is flashing while cranking.
https://www.harborfreight.com/in-line-spark-checker-63590.html
Yo Greg,
Try a Self Test for Diagnostic Trouble Codes (DTC)s by my pal, BroncoJoe19 @ Code Reader
PCM stores the Self-Test program in permanent memory. When activated, Self-Test checks the EEC system by testing memory integrity and processing capability, and verifies that various sensors and actuators are connected and operating properly.
The engine temperature must be greater than 50° F for the Key On Engine Off (KOEO) Self-Test and greater than 180° F for the Key On Engine Running (KOER) Self-Test. Run it around to heat the engine up and shift thru all gears including Reverse. Make sure A/C is off and transmission is in Park (automatic); or in Neutral for a Manual & release clutch. Then turn off engine, all accessories/lights (close driver's door) , etc.
Do KOEO test First. Post Code(s) here according to KOEO & KOER.
A helper can assist you by counting the codes. Some use their smart phones to record them.
BEWARE OF FAN, BELTS, PULLEYS, HOT HOSES, IGNITION HIGH TENSION WIRES, AND ENGINE COMPONENTS
Or ask local mom and dad parts stores if they will test it for you.
Or purchase a coder reader such as Equus 3145 Innova OBD 1 Code Reader for Ford EEC IV Engines at Walmart & most parts stores.
As Tiha advised, the Ignition Control Module (ICM) is known to overheat. If no codes or any that won't be applicable to the Issue, pull it and have it tested at most parts stores. Have them run test a few times to induce heat.
Ignition Control Module (ICM) Location pic @ distributor in an 89 5.8
Source: by Handy_andy_cv64 (Ed B)
Ignition Control Module (ICM) Removal Tips @ distributor; "...To remove the TFI = thick film integrated module you need to loosen the saftey "lock bolt" at base of the distributor so you can TURN the distributor for better access and removal but make a referecne mark so you can turn the distributor back exactly where it was otherwise you'll have to re-set the timimg so it will start and run properly. There's a special tool "ignition module socket, mfg by Powerbuilt # 648420 so you can remove the screws on the module to replace it BUT to test it you just need to turn the ignition key to the "RUN" position, engine off. don't remember what I paid for the "socket" maybe $15.00 range...?
Source: by my late friend JKossarides ("The Bronco", Jean)
Ignition Control Module (ICM) (Ford & other makes) General Descriptions; "...A major cause of failure is heat... especially typical on Ford, is intermittent failure. The car runs okay for a while, then stops. When it cools, it runs okay for a while longer. Then it stops again. And so on. This is a fairly certain indication of a heat failure fault which can be prevented from recurring by using the heat-resistant module replacement offered by us -- and you. All transistors and other solid state components have specific temperature ranges within which they work. If they go outside the temperature range, they either stop working or destroy themselves. Vibration is another enemy of the module since it causes the circuit path to break on the printed circuit board. Testing with simple, hand-held testers (figures 6) will tell the story. Every mechanic who works on domestic cars and engines needs a tester like this one. And many DIYs will have them, too. A third failure mode (figure 6) is mishandling or poor installation technique, especially with the small and somewhat fragile GM unit. It doesn't take much effort with a screwdriver, nor more than a small particle of sand or dirt on the mounting plate, to fracture the case of the GM module. In addition, heat dissipation (figure 7) is accomplished only if the right type of heat-conductive silicone grease is used between the module and the mounting plate. Poor ground connections are another failure mode. All modules must have a good connection between their cases and their mounting surfaces. A fifth failure mode is corrosion of the terminals. Bad connections fail a lot of systems. A sixth failure mode comes from applying improper voltages to the system. Most of these devices are protected from hooking up the battery or connectors backward. However, none of them is protected from over-voltage -- such as that applied when a mechanic gangs up a couple of 12-volt batteries to give an additional starting boost to a hard starting engine. Recap, Modules, used with trigger mechanisms, replace the points and condenser used in conventional contact-breaker or coil-and-breaker systems. Different manufacturers have different names for their modules. GM calls their a (module) (contacter), Ford calls theirs a (module) (modulator assembly), and Chrysler calls theirs a (controller) (control module)..." by napaechelon
1990 Ford Bronco Remote ICM Installation with some pics @ https://www.fullsizebronco.com/threads/intermittent-tfi-icm-failure.508752/#post-7256426
Try a Self Test for Diagnostic Trouble Codes (DTC)s by my pal, BroncoJoe19 @ Code Reader
PCM stores the Self-Test program in permanent memory. When activated, Self-Test checks the EEC system by testing memory integrity and processing capability, and verifies that various sensors and actuators are connected and operating properly.
The engine temperature must be greater than 50° F for the Key On Engine Off (KOEO) Self-Test and greater than 180° F for the Key On Engine Running (KOER) Self-Test. Run it around to heat the engine up and shift thru all gears including Reverse. Make sure A/C is off and transmission is in Park (automatic); or in Neutral for a Manual & release clutch. Then turn off engine, all accessories/lights (close driver's door) , etc.
Do KOEO test First. Post Code(s) here according to KOEO & KOER.
A helper can assist you by counting the codes. Some use their smart phones to record them.
BEWARE OF FAN, BELTS, PULLEYS, HOT HOSES, IGNITION HIGH TENSION WIRES, AND ENGINE COMPONENTS
Or ask local mom and dad parts stores if they will test it for you.
Or purchase a coder reader such as Equus 3145 Innova OBD 1 Code Reader for Ford EEC IV Engines at Walmart & most parts stores.
As Tiha advised, the Ignition Control Module (ICM) is known to overheat. If no codes or any that won't be applicable to the Issue, pull it and have it tested at most parts stores. Have them run test a few times to induce heat.
Ignition Control Module (ICM) Location pic @ distributor in an 89 5.8
Source: by Handy_andy_cv64 (Ed B)
Ignition Control Module (ICM) Removal Tips @ distributor; "...To remove the TFI = thick film integrated module you need to loosen the saftey "lock bolt" at base of the distributor so you can TURN the distributor for better access and removal but make a referecne mark so you can turn the distributor back exactly where it was otherwise you'll have to re-set the timimg so it will start and run properly. There's a special tool "ignition module socket, mfg by Powerbuilt # 648420 so you can remove the screws on the module to replace it BUT to test it you just need to turn the ignition key to the "RUN" position, engine off. don't remember what I paid for the "socket" maybe $15.00 range...?
Source: by my late friend JKossarides ("The Bronco", Jean)
Ignition Control Module (ICM) (Ford & other makes) General Descriptions; "...A major cause of failure is heat... especially typical on Ford, is intermittent failure. The car runs okay for a while, then stops. When it cools, it runs okay for a while longer. Then it stops again. And so on. This is a fairly certain indication of a heat failure fault which can be prevented from recurring by using the heat-resistant module replacement offered by us -- and you. All transistors and other solid state components have specific temperature ranges within which they work. If they go outside the temperature range, they either stop working or destroy themselves. Vibration is another enemy of the module since it causes the circuit path to break on the printed circuit board. Testing with simple, hand-held testers (figures 6) will tell the story. Every mechanic who works on domestic cars and engines needs a tester like this one. And many DIYs will have them, too. A third failure mode (figure 6) is mishandling or poor installation technique, especially with the small and somewhat fragile GM unit. It doesn't take much effort with a screwdriver, nor more than a small particle of sand or dirt on the mounting plate, to fracture the case of the GM module. In addition, heat dissipation (figure 7) is accomplished only if the right type of heat-conductive silicone grease is used between the module and the mounting plate. Poor ground connections are another failure mode. All modules must have a good connection between their cases and their mounting surfaces. A fifth failure mode is corrosion of the terminals. Bad connections fail a lot of systems. A sixth failure mode comes from applying improper voltages to the system. Most of these devices are protected from hooking up the battery or connectors backward. However, none of them is protected from over-voltage -- such as that applied when a mechanic gangs up a couple of 12-volt batteries to give an additional starting boost to a hard starting engine. Recap, Modules, used with trigger mechanisms, replace the points and condenser used in conventional contact-breaker or coil-and-breaker systems. Different manufacturers have different names for their modules. GM calls their a (module) (contacter), Ford calls theirs a (module) (modulator assembly), and Chrysler calls theirs a (controller) (control module)..." by napaechelon
1990 Ford Bronco Remote ICM Installation with some pics @ https://www.fullsizebronco.com/threads/intermittent-tfi-icm-failure.508752/#post-7256426
johnnyreb
Well-known member
You know your stuff Mike. After reading all that. You got my head spinning. He better write a list and check it as he goes. Thanks Mike to you and all those who served and are serving .To protect our country and freedom.
johnnyreb
Well-known member
I guess if you live alone and no one to help you. A person could buy a long piece of plug wire and be able to see it inside the cab. I have a dodge. Sometimes you have to crank it along time before it starts.Don,t know if its the pump or electrical---I,ll get that long wire and check it.
Motech
Well-known member
He sure does. I've been doing Ford driveability near 30 years and his posts make my head spin too!
This sounds like a common Ford pattern failure of a worn out Profile Ignition Pickup sensor (PIP). It's basically what used to be breaker points inside the distributor, a crankshaft position sensor (even though it's really technically camshaft position). They begin to fail with hot engine.
Quick & dirty test that shouldn't spin the head is to disconnect the SPOUT connector (Spark Output) and try again. This is the two-wire plug you remove to bypass electronic spark controls so ignition timing can be checked. This takes the load off the primary ignition signals, PIP then relaxes and speaks clearly so the ignition control module can understand it and create the "fire coil" signal.
In a nutshell, if it starts (or runs better) with SPOUT disconnected, there's a damned good chance your PIP is the culprit.
And by the way... If that is the case, shotgun all three underhood ignition controllers: PIP (or entire distributor: it's cheaper), Thick Film Ignition Control Module and ignition coil.
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