Hello, I am baffled by this problem. Can you help? I have a 1994 F-150 with a 5.8L engine. About a month ago, I was at my friends garage and got into my truck and it would not start. I had no previous problems prior to this. Since we were at the garage, we were able to determine that it was not getting any spark. Replaced the modulator, no help. Checked the coil and it was OK. My friend who is a mechanic suggested that it may be the coil or stator in the distributor. Since I need the truck on a daily basis, I had a new distributor installed. Apparently this is the only way to replace the coil under the distributor. They don't sell it separately. Well the problem was solved for about two weeks. Then the same thing happened. I stopped at a store and when I got back in to leave the truck would not start. I left the truck overnight and when I went to have to towed the next morning and tried it it started right up like there was nothing wrong. I drove it a day or so with no problem and then it happened again. No start. I figured maybe the coil was heating up and malfunctioning since it was not originally replaced. Put on a new coil. Truck started right up only to do the same thing later that day. It seems to start and run OK when it is cold. If I stop it when it is hot it will not start until it cools down usually within an hour. The distributor, modulator and coil have all been replaced. Any ideas on where to go now? Someone told me that there may be a fusable link in the wiring that is getting hot and shutting down the system. Any suggestions or ideas on how to correct this problem would be deeply appreciated. Thank you in advance.

 

Looking at your story, the truck was dead. Would not fire at all. That was the first problem, and you fixed it by replacing the distributor. Now you have a heat related problem. I think this is a different problem, and it could be caused by your new "modulator" which I assume is the ignition module on the outside of the distributor. If you still have the old one, I would put it back on and see what happens. If you have some cold spray, you could spray the module and see if it will start.

Also when you replaced the module, I am assuming if the instructions said to put heat grease on the back of it, you did put plenty on it.

 

Thank you Franklin2 for your response. Well I got the truck started when it was cold and then shut it off and plugged in the old module. The truck started right up again. I guess the old module is good. I then plugged back in to the new module. After driving the truck for about a half hour, I went home, shut off the truck and it would not start. Plugged in the old module and it still would not start. Checked for spark at spark plug, no spark. Back to the drawing board. Do you think it is a wiring problem in the harness?

 

Yours is fuel injected correct? Try to pull the codes and see if you get anything. You can do it with a testlight or voltmeter. Here's a good site to see how to do it.
Ford Fuel Injection

 

Checked the code and came up with 212 on the CM code: Loss of IDM input to EEC or SPOUT circuit grounded. I am still trying to find out what this means.

 

Ok. That's one of the signal wires going from the module to the computer. You may have a wiring problem between the module and the computer. I believe some of those wires are shielded. Make sure the shield hasn't slid up and is touching any of the terminals.

The module sends out a pulse to the computer, and the computer modifies this pulse and sends it back. That's how it controls the timing.