What would cause my 1986 F150 4x4 to stall after running for a few min and not restart for hours?

Question

the truck will run for 3-5 min after the first start it will stay running if i press the gas but stalls immediatly after the engine idals down. After the intitial start it will not restart and remain running it dies as soon as i release the key. I have changed all the related fuel system components. Now Im assuming its an electrical problem. I was lead to believe its an ignition control modual but i cant seem to locate this part under the hood. All sources Ive found says it should be mounted on the inner fender but i dont see it. Which means it may be inside the distibutor but i cant seem to identify which part of the distributor is the control modual. Any insight on what would cause this or links to web sites with 1986 ford pickup wiring scheamatics. Pictures or anything that will get me closer to figuring out whats up with my truck.

Answer 1

You have to do a few things. Verify that all visible electrical connections are clean and tight. This includes the battery, and the starter solenoid starter connections and all of the fusible links. Starter solenoid connector locations are critical. It they are not right, it won't stay running. After this is corrected, two things. First, verify spark distribution after the engine has stalled. No spark, no run. Then verify fuel pressure and delivery after the engine has stalled. If you have spark, fuel dellivery, and air supply, it will run. The ignition module is is a flat, black or gray plastic Aluminum faced rectangular solid located on the front outside of the distributor. The pick up coil is located inside. Motorcraft distributors and coils have a very hot, bright blue spark. If it is orange and weak, you have to correct it it first before you can go one. Feel the insulation on top of the pickup coil with your finger nail. If it is soft and mushy feeling, the pickup has failed. Remove the distributor and replace it with a rebuilt one or replace the pickup coil yourself. This is not a job for beginners. You are better off replacing it with a commercially rebuilt one.

There are two small relays mounted on the firewall. The master power relay has a brown base, the fuel pump relay has a green base. When you turn the ignition switch on, you will hear and feel the brown relay click( energize) as it supplies power to the entire Electronic Engine Control( EEC ) system, the fuel pump relay, which in turn supplies power to the fuel pump, and the ignition system. Three seconds later, you will hear a second series of clicks as the relays power off. The expanation is very long winded, and technical but this is the brief version. Using a test lamp, check the red or yellow wire that goes between the brown relay and the green relay as you power up the system. It should light for three seconds, then go off. Then check the pink wire as you power up the system. It should light for three seconds, then go off. If it does, go to the rear of the vehicle, find the fuel pump connector leading into the fuel tank. Insert the test lamp probe into the pink connector and energize the system. Again, the lamp should light for three seconds and then go out. You should also be able to place your hand under the fuel tank, feel and hear the fuel pump run for three seconds as it is briefly powered up. The reason this happen is to pressurize the fuel system. No fuel pressure, no run.
You must also check the ignition coil. You will need a mulitmeter to check the resistance difference between the primary and secondary circuits. If it is above or below a very specific value, replace it. You will need a manual for that specification.

If, after you have performed these checks as I've explained, it still doesn't run, I will give you more information. I will need your test notes and values to continue. It takes time to find the gremlins sometimes. Be patient. By the way, I could perform all these test within ten minutes, so if you follow instructions, it should not take you much longer.

Answer 2

I also have an 1988 F-150.Shortly after getting mine it jumped time.I wasn't totally aware what was going on.I replaced distributor,rotor button and distributor cap.Spark plugs and wires came next.Still not on the right path.Finally wised up.That is when I realized that it jumped timed.So I finally replaced the timing chain and gears.It runs great now.That is what I recommend.

Answer 3

My guess would be a coil.. being an older car with points.coils can be over looked all the time because its not something that gets changed all the time.Or maybe a condesor which is a ignition component.but I'am guessing coil,
After running and then it stops just see how hot the coil is by placing your hand on it.If hot theres ya problem.
Or when it stops check to see if it has spark at all.
Let us know how you go...

Answer 4

The control module should be located on the side of your distributor,There should be two 5.5mm bolts holding it on.There should be a wiring harness that plugs into it with 4 to maybe 6 wires.Also check your condenser,it should be located next to the coil.Sometimes the coil its self can go bad causing it to stop charging when it gets hot.Good luck I hope I was of help to you.

Answer 5

Ignotion control modual should be on the side of your distributor.
But it sounds like a classic case of fuel filter.

Answer 6

Most likely your TFI module is bad. Ford products were notorious for this defect and there was a recall because of it. If you decide to replace it yourself make sure you follow the installation instructions exactly. Clean the mating surfaces and use the heat sink grease supplied. Check the following web site to read about the problem....Good Luck...
http://www.coolcats.net/tech/troubleshooting/tfi.html

Answer 7

Ignotion control modual is bad. This is a very common failure for that year. Change it, I would bet that will fix your problem

Answer 8

Yea, I'd say replace the fuel filter, that shouldn't cost too much (maybe $20-30) and just might fix your problem.

Answer 9

check your fuel caps to see if there plugged up. fuel pump intank is pumping against vacuum .