About a month ago i was driving my 1985 f250 and it just cut out, i pulled over and attempted to start it again, i had just filled up the tank so i know it didn't run out and i took the air cleaner off and hit the throttle and saw the gas spaying in, when i turned the key it would crank fine. so i towed it home, the next day i replaced the ignition coil, and it started right up, and i drove it up the street and it cut out on me again, i costed back down and jumped it and it started again, i started for a couple of days after that. then i went to work and after about 4 hours i went to start it again and it wouldn't start, i started it at the end of the day and it fired right up. A few days later i went to the store and it wouldn't start when i came out. i Then replace the ignition module in the distributor. It started right up after that. About a week later the same thing happened. I waited 2 hours and went back and it started right up. Does anyone have any idea what might be the problem. Every time it does this it turns over and is getting gas but it will not fire, any input would be greatly appreciated, Thanks

 

You should tell us what year your truck is, what engine and fuel system it has, what ignition it has, etc. The best way to do that is by placing it in your sig. Otherwise we have to ask every time you post.

In any event, I'm going to assume it is a DS-II with an ignition module on the driver's fender liner. And, I think that is the problem. It is failing intermittently, and that's not unusual for them.

 

Yes, it's a silver looking box with wires going to the distributor. I think it's the problem too.

 

Its a 1985 F250 single cab, 8 foot bed, 30k miles, 351, 4 speed with a zf5 now. it has the factory carb on it the only thing on the motor is the headers. It doesn't have the module on the fender it as the one on the distributor and i have replaced that.

 

Oh, you have the TFI ignition, which is known to fail. But, you said you replaced it and the coil. You then need to do some troubleshooting when it fails. One approach is to determine if the TFI module is getting power. Then find out if it is pulsing the coil and if the coil has power to it. Unfortunately I don't have wiring diagrams for TFI so I can't tell you what connections to check. Hopefully someone else will come along with access to the diagrams.

 

IIRC both the Chilton & Haynes books have some decent ignition troubleshooting diagnostics in them.

 

This truck has California emissions on it? I am not fond of the computerized carb systems, even though they worked ok when new.

 

It's a 'light' 250.
Under 8,500 gvw with TFI and a two barrel.
That's not just Cali....

 

He is susceptible to the same problems they guys with the computer sixes are. If everything is left alone and is working, fine. If someone has been jerking hoses and wires off under the hood, he has problems he might not know about. I know the headers are messing up his EGR system, but it may not care too much about that. He might run into a pinging problem though.