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Hey all!
I have a 1986 Bronco 5.0 FI 4 speed no O.D. and it has an impossible fault. When my truck is cold, she starts just fine. No hesitation in any way. However, once I've driven for a few minutes and it has an opportunity to warm up, it hardly turn over until it's cooled down again. When attempting to start it, it acts like the battery is dead. It will turn over incredibly slow, about a single revolution per second. Not nearly quick enough to fire. Sometimes if I'm lucky, it'll kinda 'catch' and fire right up. Not commonly, though. If I'm able to pop/bump start it, it'll fire right up. Jumping the battery does nothing.
This is obviously a pretty big problem, especially considering it takes between 0.5-2 hours to cool down enough to start again. It is a manual transmission, and I have 35" tires with the stock 3.55 gearing, so it isn't difficult to kill. I just can't trust it to drive.
I have tried many different approaches to fixing the problem. New starter, starter wire, starter solenoid, battery leads, battery, and alternator. Because it has extreme reluctance to actually turning the motor over, but no problem running after pop starting it, I'm sure it has nothing to do with the ignition. However, I've still installed new plugs, wires, cap, rotor, both fuel pumps, and ignition module. Nothing made any difference.
I thought it may be a pulley on the serpentine pattern possibly heating up and causing drag. I inspected all of the pulleys, and they all looked fine other than the A/C compressor. I took the V belt off of it, and tried again. Nothing.
I start it in neutral with the clutch in, but I've tried it with the clutch out as well. (Faulty clutch depression switch) Nothing makes a difference.
I am so sick of blindly replacing parts, and it's time to farm this out. I really hope someone can give me any other ideas, because I'm completely out.
Thanks in advance!!
/Quinn
I have a 1986 Bronco 5.0 FI 4 speed no O.D. and it has an impossible fault. When my truck is cold, she starts just fine. No hesitation in any way. However, once I've driven for a few minutes and it has an opportunity to warm up, it hardly turn over until it's cooled down again. When attempting to start it, it acts like the battery is dead. It will turn over incredibly slow, about a single revolution per second. Not nearly quick enough to fire. Sometimes if I'm lucky, it'll kinda 'catch' and fire right up. Not commonly, though. If I'm able to pop/bump start it, it'll fire right up. Jumping the battery does nothing.
This is obviously a pretty big problem, especially considering it takes between 0.5-2 hours to cool down enough to start again. It is a manual transmission, and I have 35" tires with the stock 3.55 gearing, so it isn't difficult to kill. I just can't trust it to drive.
I have tried many different approaches to fixing the problem. New starter, starter wire, starter solenoid, battery leads, battery, and alternator. Because it has extreme reluctance to actually turning the motor over, but no problem running after pop starting it, I'm sure it has nothing to do with the ignition. However, I've still installed new plugs, wires, cap, rotor, both fuel pumps, and ignition module. Nothing made any difference.
I thought it may be a pulley on the serpentine pattern possibly heating up and causing drag. I inspected all of the pulleys, and they all looked fine other than the A/C compressor. I took the V belt off of it, and tried again. Nothing.
I start it in neutral with the clutch in, but I've tried it with the clutch out as well. (Faulty clutch depression switch) Nothing makes a difference.
I am so sick of blindly replacing parts, and it's time to farm this out. I really hope someone can give me any other ideas, because I'm completely out.
Thanks in advance!!
/Quinn
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