my 97 f150 cut off on me today driving down the road. the truck will not spark. i have replaced the coil pack with two new coils. replaced the crankshaft sensor and tried checking wiring. i found that there was still no spark to the coil pack. has anyone ever had this problem and what could be the problem???? thanks

 

holy cow, didnt think it was possible with all i've heard. i just went through this same problem the past 2 weeks. replace your computer. i did everything you did, and got noware. i ordered a new computer and she started right up. hope it helps.

 

this may be a dumb question pfd843 but, would it be worth trying to replace the camshaft sensor before the ecm? i looked around and i've gotten that i should try to replace the camshaft sensor first rather then the ecm. do u think its worth it, or did this EXACT same problem happen to you and if it did, then it soiunds like the computer would be best

 

There are several things that can cause a no spark condition including the PCM. Sugesting that it be replaced when there is no evidence of diagnostic tests performed is an expensive disservice.

The camshaft sensor will not cause no spark condition.

Have you verified power to the coils? There are a couple of RFI caps that I see that short out and blow a fuse and cause this fault. Look at F30 in the underhood fusebox.

The 97 4.6 has a pretty simple ignition system. Crank sensor feeds into the PCM, the PCM fires the coils. Before condemning the PCM, make certain that you have verified all PCM power inputs, coil power supply circuit, and the wiring harnes conntions between the PCM and the CKP and the coils.

Steve

 

like project said, i would check all fuses, diodes and relays first. get a test light and check for a signal on the 2 outer wires on the coil plug and 12 volts on the middle wire. i checked all those things on mine, and when it came down to it, the computer was bad. it starts now but i have a miss to. but its better than it was. at least it started.