FE Build 1989 5.0 won't start when hot except when using starting fluid

JoeysAutos

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Any update on your troubleshooting efforts. I'm having the same issue you are with my '91 5.0, been fighting with this for weeks now (no start when hot). I have to let here sit for a few mins before she's able to start again. I would have no spark, no injector pulse. Fuel pressure is fine. Motor spins over fine. I've gone through the checklist multiple times, no success. The only thing I have not tried is relocating the tfi module.
PLEASE get ahold of me if you fix this. Sadly I don't have any ideas but I'm trying my heart out to pull some ideas out of these fine gentlemen here.

10* before top dead center?
A retarded or should I say ignition impaired engine is not easier to start.
Yes, 10* BTC. Generally speaking if the timing is off in any direction you want it to be retarded rather than advanced. Obviously you don't want it off at all. If you really think setting it to 12* or 14* will help I can try it because like I said I own a timing light now lol. 10* BTC is what it says on the sticker in my engine bay though.
 
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JoeysAutos

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Any update on your troubleshooting efforts. I'm having the same issue you are with my '91 5.0, been fighting with this for weeks now (no start when hot). I have to let here sit for a few mins before she's able to start again. I would have no spark, no injector pulse. Fuel pressure is fine. Motor spins over fine. I've gone through the checklist multiple times, no success. The only thing I have not tried is relocating the tfi module.

new coil
new solenoid
new distributor
new ect
checked and cleaned all grounds
tried different ignition switch (even though there was no obvious reason to)
tried different computer
timing is set
cranks fine when cold
I just reread your comment and noticed that you don't have spark when in nostart condition. That really sounds like classic PIP sensor to me, I've heard multiple stories of people getting dud brand new PIP sensors before, so if it's not too late to return the distributor for a refund and stick another new one in than that's what I'd do. If you're past the return window then maybe just stick around and see if we uncover anything
 

90sickfox

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I don't see a huge problem towing cars that aren't as heavy as your behemoth....with a tow dolly. With a dolly a bunch of that weight is still on the rear axle of the car. It also cuts out a bunch of trailer weight. Also, no tags needed for a dolly. A badlands winch from HF and a dolly can really get some stuff done. If you're really good " like I was " you could chock the rear wheels of the car, put the car in neutral, and push the dolly right under the front wheels ".

I speak from experience....the truck would do it better.

Hot no starts are a PITA.
 
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JoeysAutos

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I really appreciate all the towing advice guys, really. I understand you're just looking out for a guy. I only brought it up because I wanted to explain why I was saving this chassis. I used to be a tow truck driver. I'm gonna be careful. I know about weight distributing hitches, dollies, helper airbags, all that. I think we can all agree, I'm not gonna die just because it's not a pickup truck. If I die towing with this car it will be due to my own negligence. Thanks everyone for the concern.

This thing is never going to see the road if it can't hot start anyway so I just want to refocus this thread back on that for the time being.
 
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$wine

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Yes pip seems to be the at fault component here. I have 2 new distributors not worth the effort to seek replacements. I do know for sure that all 3 of the new TFI modules I got are not good (the tfi that came with each dizzy and 1 that I bought separate). My original tfi (motorcraft) is what I have on one of the new dizzy and has been the only tfi to consistently allow the car to start (when cold) and run without cutting off for up to 1hr. All the others after 15-20 mins the car cuts off no warning. No restart after that at all (hot, warm or cold). I would have to swap dizzy and start over.
My next plan of action is to try the motorcraft tfi on the other new dizzy.
 

$wine

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Yes pip seems to be the at fault component here. I have 2 new distributors not worth the effort to seek replacements. I do know for sure that all 3 of the new TFI modules I got are not good (the tfi that came with each dizzy and 1 that I bought separate). My original tfi (motorcraft) is what I have on one of the new dizzy and has been the only tfi to consistently allow the car to start (when cold) and run without cutting off for up to 1hr. All the others after 15-20 mins the car cuts off no warning. No restart after that at all (hot, warm or cold). I would have to swap dizzy and start over.
My next plan of action is to try the motorcraft tfi on the other new dizzy.
Well that was a fail. Same result as the other dizzy. Started right up, ran for 45mins, I cut it off and no hot start. Let her sit for about 5 mins and starts up fine.

One observation during hot start attempt. Some times it cranks really strong (no spark or injector pulse) then sometimes it cranks as if the battery is weak, that slow drag like the battery is about to take its last breath. The battery is fine, I took it to have it tested to confirm. There’s also sometimes it cranks strong for like 3 attempts and then the slow crank, let her sit for a few mines and she cranks strong and starts.

I’m really afraid to take this car out on the road. When this all started the car died on me doing 70mph on the interstate, left me stranded for 2.5 hours. Even though it’s been consistently restarting after letting her cool down. Temp is normal.

Thoughts?
 

JoeysAutos

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Everything you're describing sounds VERY similar to the problems that I'm having, aside from the TFI issues with the car cutting out and not restarting. My car does that exact thing when hot, seems like once the temp gauge dips below 160f after 10min or so mine will restart. Does yours restart with starting fluid when hot or no?
 

$wine

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Everything you're describing sounds VERY similar to the problems that I'm having, aside from the TFI issues with the car cutting out and not restarting. My car does that exact thing when hot, seems like once the temp gauge dips below 160f after 10min or so mine will restart. Does yours restart with starting fluid when hot or no?
I have not tried that as I’m not getting any spark so ......
I have inline spark tester between coil and cap, fuel pressure gauge on a schrader valve and noid light on injector harness. When it’s warm/hot start there’s no injector pulse and no spark. Definitely something that is temperature related. I’ll try pulling codes tomorrow.
 

$wine

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Everything you're describing sounds VERY similar to the problems that I'm having, aside from the TFI issues with the car cutting out and not restarting. My car does that exact thing when hot, seems like once the temp gauge dips below 160f after 10min or so mine will restart. Does yours restart with starting fluid when hot or no?
It only cut off on me the one initial time while driving. Since then it’s just been idling when it cut off after 15-20 mins or so. Thats mot happening anymore. Just not starting when warm/hot now.
 

JoeysAutos

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Okay, well this is making me want to triple check on my spark now because it's so odd that we have the same issue except that I have spark still. Like maybe the starting fluid is auto-igniting or something. Also I think I'm going to clean every single contact on my starter solenoid while I'm in there for the heck of it. Please update us on codes especially if you're doing the KOER test that'd be great to know what you find
 

JoeysAutos

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Alright I asked the Lincoln guys what they thought and they gave me some great info courtesy of the Ranger guys. This sounds like it should really help you $, if you haven't found this info already. I haven't gotten a chance to do this yet but this is what I'm doing today. Here's the full quote from the Lincoln forums:
So there are two power sources for the TFI module, one is crank power, the other is key-on power. I'm betting either you do not have crank power, or the module happens to be junk and the crank power input is not actually working. I don't have the manual in front of me but reasonably sure with no power into (or through) the TFI module, the PIP doesn't function so you get no PIP signal to the ECM.

first thing I'd suggest doing is unplugging the TFI and seeing if you have power at pin 3 with the key on, and pin 4 when cranking

TFI_ignition_system.gif


The rest of that page has good info on troubleshooting the ignition system but without power none of this is going to work right.

https://www.therangerstation.com/tec...agnostic.shtml

Highly recommend checking that link out for tons of troubleshooting info on the TFI system
 
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$wine

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Alright I asked the Lincoln guys what they thought and they gave me some great info courtesy of the Ranger guys. This sounds like it should really help you $, if you haven't found this info already. I haven't gotten a chance to do this yet but this is what I'm doing today. Here's the full quote from the Lincoln forums:


Highly recommend checking that link out for tons of troubleshooting info on the TFI system
Can’t believe I missed the notification for this post all weekend. I’ll test for power at pin 3 and 4 when I have a warm/hot crank no start. However, my car will start and run when below a certain temp, and continue to run until I turn it off. I’ve tested this for up to 1hr. My car will only start back up after it has cooled for about 5mins. During the no start period temp gauge is normal, fuel pressure is 35-40, no injector pulse, no spark. I’m not confident in her enough to take out on the road at this time.

I’m also in the process of rebuilding my original distributor, so any one reading this post have a recommendation for a good quality brand pickup coil, please share info.

I pulled codes this weekend. Car was warmed up first.
KOEO - 34 - EGR valve circuit out of self-test range.
Running - no code.(engine revved at 2000rpm for about 30 secs I think then dropped and idled at normal)

Mods-
(1) smog pump deleted (was seized up)
(2) egr deleted with the delete dongle attached. http://rover.ebay.com/rover/1/711-5...0001&campid=5335821607&icep_item=264314940770

1991 V8 AOD GT swapped into 1991 2.3L LX Coupe

My no start when warm/hot was happening before the egr delete. The smog pump was found seized during the swap and bypassed. Now completed deleted.
 

JoeysAutos

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I see you under my last post, jrichker. Your guides have helped me immensely. :hail: Please bless us with your insight.

While engine was in no-start condition I tested for power on those pins while in Run and Start and they both are within spec. Also tested for continuity between the PIP pin 6 on the TFI harness and pin 56 on the ECM and found they have a good connection, 0.65ohms. Also, tested for spark with an inline spark tester and it's got great spark while in no-start condition. The Lincoln guys I'm talking to believe this means the PIP is working since there's spark, and the computer is getting the PIP signal since there's a good connection, but somehow the computer is failing to give ground pulse to the injectors. So far the only guess they have is voltage drop issue, but I'm not too sure what I need to test next to verify this. I did try cleaning up all the connections on the starter relay and battery terminals but this had no effect.

However, my car will start and run when below a certain temp, and continue to run until I turn it off. I’ve tested this for up to 1hr. My car will only start back up after it has cooled for about 5mins.

Mine acts exactly the same way. Very odd how it could seemingly continue to operate indefinitely just fine as long as it never turns off. Really makes a guy suspect of the Start circuit.
 

jrichker

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I see you under my last post, jrichker. Your guides have helped me immensely. :hail: Please bless us with your insight.

While engine was in no-start condition I tested for power on those pins while in Run and Start and they both are within spec. Also tested for continuity between the PIP pin 6 on the TFI harness and pin 56 on the ECM and found they have a good connection, 0.65ohms. Also, tested for spark with an inline spark tester and it's got great spark while in no-start condition. The Lincoln guys I'm talking to believe this means the PIP is working since there's spark, and the computer is getting the PIP signal since there's a good connection, but somehow the computer is failing to give ground pulse to the injectors. So far the only guess they have is voltage drop issue, but I'm not too sure what I need to test next to verify this. I did try cleaning up all the connections on the starter relay and battery terminals but this had no effect.



Mine acts exactly the same way. Very odd how it could seemingly continue to operate indefinitely just fine as long as it never turns off. Really makes a guy suspect of the Start circuit.

You may not have a code 14 but still have a PIP sensor problem. The information here on Stangnet points to a deteriorating quality of PIP sensors and TFI modules. It is not uncommon to get several new DOA or marginal electronic parts right out of the box.

Code 14 - Ignition pickup (PIP) was erratic – the Hall Effect sensor in the distributor is failing. Bad sensor, bad wiring, dirty contacts. Factory tach will sometimes read erratically.

Revised 8-Apr-2017 to correct SPOUT problem symptoms wording

The PIP is a Hall Effect magnetic sensor that triggers the TFI and injectors. There is a shutter wheel alternately covers and uncovers a fixed magnet as it rotates. The change in the magnetic field triggers the sensor. They are often heat sensitive, increasing the failure rate as the temperature increases.

PIP Sensor functionality, testing and replacement:[
The PIP is a Hall Effect magnetic sensor that triggers the TFI and injectors. There is a shutter wheel alternately covers and uncovers a fixed magnet as it rotates. The change in the magnetic field triggers the sensor. A failing PIP sensor will often set code 14 in the computer. They are often heat sensitive, increasing the failure rate as the temperature increases.


Some simple checks to do before replacing the PIP sensor or distributor:
You will need a Multimeter or DVM with good batteries: test or replace them before you get started. You may also need some extra 16-18 gauge wire to extend the length of the meter’s test leads.
Visual check first: look for chaffed or damaged wiring and loose connector pins in the TFI harness connector.
Check the IDM wiring – dark green/yellow wire from the TFI module to pin 4 on the computer. There is a 22K Ohm resistor in the wiring between the TFI and the computer. Use an ohmmeter to measure the wire resistance from the TFI to the computer. You should see 22,000 ohms +/- 10%.
Check the PIP wiring - dark blue from the TFI module to pin 56 on the computer. Use an ohmmeter to measure the wire resistance from the TFI to the computer. You should see 0.2-1.5 ohms.
Check the SPOUT wiring – yellow/lt green from the TFI module to pin 36 on the computer. Use an ohmmeter to measure the wire resistance from the TFI to the computer. You should see 0.2-1.5 ohms.
Check the black/orange wire from the TFI module to pin 16 on the computer. Use an ohmmeter to measure the wire resistance from the TFI to the computer. You should see 0.2-1.5 ohms.
Check the red/green wire; it should have a steady 12-13 volts with the ignition switch on and the engine not running.
Check the red/blue wire; it should have a steady 12-13 volts with the ignition switch in Start and the engine not running. Watch out for the fan blades when you do this test, since the engine will be cranking.
If you do not find any chaffed or broken wires, high resistance connections or loose pins in the wiring harness, replace the PIP sensor or the distributor.

The PIP sensor is mounted in the bottom of the distributor under the shutter wheel. In stock Ford distributors, you have to press the gear off the distributor shaft to get access to it to replace it. Most guys just end up replacing the distributor with a reman unit for about $75 exchange

PIP problems & diagnostic info
Spark with the SPOUT out, but not with the SPOUT in suggests a PIP problem. The PIP signal level needs to be above 6.5 volts to trigger the computer to pulse the fuel injectors, but only needs to be 5.75 volts to trigger the TFI module. Hence with a weak PIP signal, and the SPOUT in, you could get spark but no injector pulse. You will need an oscilloscope or graphing DVM to measure the output voltage since it is not a straight DC voltage.

Also look at the TPS voltage since a TPS voltage over 4 volts shuts off the fuel injectors when cranking. This helps to clear a flooded engine condition, since the temporary fix to start a flooded engine is to press the accelerator all the way to the floor.
 
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Mustang5L5

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My no start when hot was an ECT sensor. Way to test this is that when the car isn’t starting, depress the gas pedal to the firewall and crank. This is “flood clear” mode. If it starts, it’s signs of a bad temp sensor.

you would also have a code stored in the ECU if you pull codes
 

$wine

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Higher end scanner (Snap on Solus) would have helped diagnose ECT sensor.
GT - Parameter Identification (PID) - Typical Diagnostic Reference Values.

Good job fixing mustang, congratulations and thanks for sharing.
Can’t believe I missed the notification for this post all weekend. I’ll test for power at pin 3 and 4 when I have a warm/hot crank no start. However, my car will start and run when below a certain temp, and continue to run until I turn it off. I’ve tested this for up to 1hr. My car will only start back up after it has cooled for about 5mins. During the no start period temp gauge is normal, fuel pressure is 35-40, no injector pulse, no spark. I’m not confident in her enough to take out on the road at this time.

I’m also in the process of rebuilding my original distributor, so any one reading this post have a recommendation for a good quality brand pickup coil, please share info.

I pulled codes this weekend. Car was warmed up first.
KOEO - 34 - EGR valve circuit out of self-test range.
Running - no code.(engine revved at 2000rpm for about 30 secs I think then dropped and idled at normal)

Mods-
(1) smog pump deleted (was seized up)
(2) egr deleted with the delete dongle attached. http://rover.ebay.com/rover/1/711-5...0001&campid=5335821607&icep_item=264314940770

1991 V8 AOD GT swapped into 1991 2.3L LX Coupe

My no start when warm/hot was happening before the egr delete. The smog pump was found seized during the swap and bypassed. Now completed deleted.
I pulled codes again. I let the car warm up to temp where it won’t restart and performed the koeo test. Then after about 5mins reatarted and performed koer test so it would still be warmer than a cold start.
KOEO - 34
KKOER - 19, 34, 44
Thoughts in reference to crank no start when warm/hot?
 

Mustang5L5

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19 (O) No Vehicle Power (pins 37 + 57) or bad PCM
(R) Erratic idle during test (reset throttle & retest)
Electronic ignition Cylinder ID sensor/circuit problem


34 EVP - (R) EGR did not respond properly during test EVR - (O, R, M) EVP sensor is/was high PFE - (O, R, M) PFE sensor is/was out of range

44 is the air pump system inoperative.
 

$wine

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19 (O) No Vehicle Power (pins 37 + 57) or bad PCM
(R) Erratic idle during test (reset throttle & retest)
Electronic ignition Cylinder ID sensor/circuit problem


34 EVP - (R) EGR did not respond properly during test EVR - (O, R, M) EVP sensor is/was high PFE - (O, R, M) PFE sensor is/was out of range

44 is the air pump system inoperative.
34 and 44 would make sense as my smog pump and egr are both deleted. As for 19 what’s considered erratic? Idle is ~750. It goes up maybe to 900 then back to 750 every ~45sec