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Discussion Starter #1
Basically as the title says. I had an issue getting the Bronco to start a week ago and thus had to leave it sitting for a few days. I assumed it had flooded and had a very busy weekend so couldn't get back to it. When I got back it fired right up and I drove home. I proceeded to drive it all week and then went out of town so the Bronco sat for a few more days at a friend's house. On my way home it died at 35mph and I had to pull over and couldn't get it started again.

Issue:
I took the wire that goes from the coil to the distributor and put a spare spark plug in it and fired cranked the engine a few times. I noticed that both times it wouldn't start that it'd only give the slightest attempt to start when I let off the starter. This made sense when that spark plug would only spark when I let off.

The next day, the ignition control module was tested and it failed 4/5 tests. Swapped that out and it fired right up. I figured that was it until I went to drive somewhere that evening and had the same issue. I looked at the leads coming from the distributor and one of them had a 1" long bare section (I guess colored electrician's tape doesn't hold as long as black) that was up against a bracket. I wrapped that up and it fired right up.

Again, I assumed that was it but then when I went to drive it home from where I was at the exact same issue arose again - spark only when I let off the starter. I thought perhaps the grounding out of that wire ruined the ICM again but it passed all the tests several times this time.

Has anyone had an issue like this or have any ideas? Thank you.
 

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Kitteh Commandaar!
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Check your connections to/from the battery. My bronco did the same thing on occasion...would turn over fine, and as soon as you let off the key, the engine would fire a time or two, but not enough to stay running. Basically I gave it a jump an it still wasn't enonugh. Cleaned all the connections, and workin ever since. The way I figured is that the starter is pullin all the juice, and there wasn't enough to fire the ignition system.

Have the battery load tested too, might be going south on you. I know my battery wasn't the best either...

KC
 

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i had that happen during an engine swap once. Check your ground connection to the body. my harness was hacked up from the swap but believe somewhere close to the ecm.
 

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It looks like you have "363" W, ie: modified 351......?

If it's EFI then go directly and pull codes from the vehicle computer and perform tests *KOEO and KOER if necessary to see what "faults" show up in Continuous Memory.....go here for FREE code numbers, explanations and How To......for your 86 BKO you'll need the OBD-1 Ford Code Reader with diagnostic book which costs $29.99 at O'Reillys OR there is a "code pulsing technique" but IMO it's a PITA...using a paper clip......

Check the wires off the harness for the grey plastic connector that goes to the ignition coil, poor wiring there could be an issue as the wire ends snap into the plastic connector and can become loose inside, the plastic "lock nubs" inside might be worn a bit and not hold the brass end of the wire...easily overlooked.......you can get a pigtail connector at fordfuelinjection for $12.00 or most auto parts stores if needed..

I hate to say this but brand new TFI modules can be bad from the get go even when tested.....but don't overlook the PIP = profile ignition pickup on the end of the distributor...can be bought seperately or get a reman Dissy from Napa with the TFI and PIP ready to go out the for around $130.00, 1 yr warranty last time I checked, either way you'd need to pull the dissy out...

Check/clean ALL wires and cables that converge on the "starter relay" you need a clear continuity path without any resistance AND make sure the ignition wire on the relay is on securely and in good condition...ground your NEG battery cable to the frame for additional continuity...

Check the FPR = fuel pressure regulator up top on the fuel rail towards the back, you'll need a fuel pressure guage to check PSI but for quick check there's a schraeder valve on the rail towards the front, looks like a tire valve so push the center in and see if any fuel comes out..

Just a few thoughts.....:doh0715:


Good Luck ~ :thumbup
 

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Discussion Starter #6
Thanks for the replies guys. They're appreciated as always. I'll give those a try and see how it goes.

As for the "363" it's just been bored over by 0.06" but it is a 4bbl carb.
 

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Have you tried checking the pickup inside the coil? That was my problem when mine would die at random times. Turns out the pickup harness was corroded and after I replaced that, haven't had a problem since. But I do agree with everyone about your battery connections, after you clean those really good it should feel like a new car lol.
 
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