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Discussion Starter #1
Ladies and Gentleman,
This is a new issue I do not have a clue as to what is wrong, please assist. Driving 45 mph on way home from job and engine just shuts off. No warning, no nothing! So could this be some kind of electrical problem, or what???
 

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With no prior warning signs it is usually electrical. Since I'm on my third fuel pump... I would lean towards the fuel pump. Does the pump prime when the key is turned to ACC? I read a post where a guy stated that... just like a starter motor sometimes a good bump can get the electrical fuel pump working again. Good luck trying to get the top of the tank.. unless you have an access already cut in the bed.
 

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Discussion Starter #3
With no prior warning signs it is usually electrical. Since I'm on my third fuel pump... I would lean towards the fuel pump. Does the pump prime when the key is turned to ACC? I read a post where a guy stated that... just like a starter motor sometimes a good bump can get the electrical fuel pump working again. Good luck trying to get the top of the tank.. unless you have an access already cut in the bed.
Mr. Rondelli,
I am not sure, but I do not think my 1987 Bronco has an electrical fuel pump.
 

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95 Bronco, 351W, E4OD, 4.56 gears, 35x12.50x15 Patagonia MTs.
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All 87-96 Broncos were fuel injected. Check for spark and fuel pressure and let us know what you find. The fuel rail will have a schrader valve on it, depress the center carefully and fuel should spray out. Might want to cover it with a towel and use eye protection.
 

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Discussion Starter #5
All 87-96 Broncos were fuel injected. Check for spark and fuel pressure and let us know what you find. The fuel rail will have a schrader valve on it, depress the center carefully and fuel should spray out. Might want to cover it with a towel and use eye protection.
Thank You for the information, I knew it had fuel injection but did not know a electric fuel pump was required. You guys are expanding my mechanical knowledge immensely. I have it at the mechanics shop now, I will mention it to them.
 

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Yo @Lamps3
How's it going? I missed this post!

Does it crank over and start now?
OR just cranks but no run?


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.

Inspect the air cleaner and inlet ducting. KCheck all engine vacuum hoses for damage, leaks, cracks, blockage, proper routing, etc. Check EEC system including the wiring harness for proper connections, bent or broken pins, corrosion, loose wires, proper routing, etc. Check the Powertrain Control Module (PCM), sensors and actuators for physical damage. TPS, ICM, DISTRIBUTOR, etc. Check the engine coolant for proper level and mixture. Check the transmission fluid and engine oil level and quality. Make all necessary repairs before continuing with SELF TEST.

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 and; 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 and 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 I Code Reader for Ford EEC IV Engines at Walmart & most parts stores.
 

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The 351w wasn't fuel injected until 1988.

However, the 302 (which your signature says you have) went fuel injection in 1985, so you definitely have an electric fuel pump.

The only time I've had one of these engines straight up 100% die while driving was when the distributor gear sheared a pin. You can quickly test this by taking the cap off the distributor and see if you can rotate the distributor shaft. (Hint: it shouldn't spin freely)

If so, it'll need a new install a new pin. You'll also want to see why it failed. Most often it's due to the oil pump going out, which causes a lot of resistance. Since the distributor also spins the oil pump, a sluggish oil pump will eventually fatigue the pin on the distributor gear and snap it. You can test this by getting an 8mm hex socket on the end of an extension and spin by hand. It should be easy to turn.
 

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'95 XLT: 5.8/MAF/E4OD/6" lift/4.56's/33x12.5x15
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Another issue I've experienced with the EFI Bronco dying while driving but being able to re-start and drive on was a bad TPS (Throttle Position Sensor).
You didn't say anything about performance after it died, so this may or may not apply.

I had another die and refuse to re-start and that was a bad rotor, threw the tip and destroyed my PIP sensor inside the distributor.
Details matter, especially with online diagnosis.
 

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Discussion Starter #9
Well Everyone, it ended up being an ignition module. Seems for this particular year which has the location above the engine it is a problem for all concerned!!! Thank you for the suggestions on what to check.
 

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That's interesting, I've never really heard of an ignition module just "going out" mid-flight. Usually, they exhibit a slow death, beginning with difficulty starting the engine when it's hot.

Glad you figured out what it was!
 

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FYI your 87 has 2 fuel pumps. One in the Tank and one inside the frame rail in line with the front of the drivers side door.
 

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95 Bronco, 351W, E4OD, 4.56 gears, 35x12.50x15 Patagonia MTs.
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28 Posts
The 351w wasn't fuel injected until 1988.

However, the 302 (which your signature says you have) went fuel injection in 1985, so you definitely have an electric fuel pump.

The only time I've had one of these engines straight up 100% die while driving was when the distributor gear sheared a pin. You can quickly test this by taking the cap off the distributor and see if you can rotate the distributor shaft. (Hint: it shouldn't spin freely)

If so, it'll need a new install a new pin. You'll also want to see why it failed. Most often it's due to the oil pump going out, which causes a lot of resistance. Since the distributor also spins the oil pump, a sluggish oil pump will eventually fatigue the pin on the distributor gear and snap it. You can test this by getting an 8mm hex socket on the end of an extension and spin by hand. It should be easy to turn.
The 351W was fuel injected as of 1986 in CA.
 

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I know I had the power box go out on me. While I was driving down the road. Sometimes they will start back up. I done away with it and put a point distributor in it. Its not fun hauling 12 ton down hill and your motor quits. I don,t like this new electronic stuff.
 
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