I give up. And it did, too.

[Randee of the Redwoods]

On the way back from Pep Boys today, the engine just quit, then resumed right back where it left off. While sitting in the driveway idling, it has developed a random, infrequent miss(stumble?). I give up. I have rehabbed almost the entire electrical system. I've researched stalling problems related to fsd's. I've checked for codes and got none that were "relative" to a failing fsd. I give up. I just can't fix this thing and the trouble is not repeatable on demand so I can't isolate it. I don't have the money to go and buy replacement parts for the process of elimination. Runs fine, then will randomly give me a hard time, but it has always restarted. I would like to note that I start the truck from a starter button because the key start stopped working. Could the problem be the ign key??????? 196k miles and counting so it's well worn. I need some options or suggestions on things to try to isolate the problem. I just give up. Everything I do to isolate the problem makes it worse, but I still can't find it. If you're interested, I'm taking offers for sale.
I'm not above replacing such systems as the pmd or larger, but I just can't figure out how to determine if THAT is actually causing the problem.
And currently I can't afford the "hit or miss" it's gonna take. Damn this truck and my love for it. I'm ready to convert to mechanical injection if I knew that would solve my problems.

[john8662]

I vote ignition switch, solely on the "push button" starting you mentioned.

I replaced the ignition switch on my 95 and it made a difference affecting other electrical grimlens, but I haven't torn into the 94 column. I believe the switch is not in the tumbler itself as it is in the 95+ models but, it's sitting somewhere down below. I'm sure someone on here (probably after Chirstmas time) will have the "been there done that" experience to speak about the 94.

If you suspect the FSD, perhaps you could acquire a used FSD just to try, because afterall they ain't gonna generate a code when they fail.

[Randee of the Redwoods]

I'll add more details I may have left out in my frustration.
Jiggling key while running makes no difference. Engine still runs. Lift pump seems to be working fine based on amount of fuel pouring out of filter housing while priming filter. Fuel filter has been relocated and all engine mounted fuel lines except for one return line have been replaced. Fixed a nasty kink in the supply line to the ip as well. Actually runs better now. Cleaned out all connections at back of motor and filled them with dielectric grease. Added a ground strap from the fire wall to the motor. Relocated 4 motor grounds to the same spot. Added ground from motor to frame rail.
I'll dig up a new ign switch. I have dealer service manuals that should show me how to replace it. Monday I'll disconnect the batts and clear the computer. Yes, that's the day after Christmas, but it's going to like 50*F.

[Shuck]

Just more information on the ignition switch - jiggling the key didn't make my symptoms appear or disappear, but it was the problem. It might be worth a look, even though jiggling the key doesn't make a difference. I had a remote start which made troubleshooting my problem easy, but might not hurt to poke around with a voltmeter.

[Randee of the Redwoods]

Is the ign switch a thing I can get anywhere or is this a dealer item?

[5.7L oldsdiesel]

You can get them at most autoparts stores for something like $20 bucks.The dealer is'nt necessary.

[Randee of the Redwoods]

Just a thought. To rule out the ign harness, could I just hot run the fuel shutoff solonoid straight to the battery, maybe even through a switch, so as to run the motor with the solonoid bypassed out of the ign harness? My guessing is that if my problems stopped, then I'd have narrowed down my problem. Just a thought.