1989 Pickup 22RE
 

I would like to start off by saying I have found a ton of useful information over the years here that has helped me tremendously and now I have a situation that I can't figure out.
What I have is a 1989 Toyota Pickup, 22RE that will just die, it wont sputter, it just dies. I throw a spark tester on there from the coil or any cylinder, and it has lost all spark. I have had many used parts that I have swapped and seem to make a difference for a short period of time. I have swapped the igniter, Coil, Wires, Mass Air Flow Meter, Distributor, New Cap, New Rotor. Now I have another 89 pickup with the same 22RE that is running great. I have swapped all these same parts again, including the computer, with the same result. Any ideas of what I could be missing?

Thanks in advance.

Checked for continuous correct fuel pressure???

Yes, I forgot to mention that. I changed the fuel pump, and hooked up a fuel pressure tester to it ran it up through the hood and watched it the whole time. Fuel is great, spark just disappears. I even ran a jumper wire to the coil and still don't have spark. I almost think it's heat related, something is heating up and killing the spark.

Something is heating up and killing a wire I'd say. Go wiggle stuff? I'd start testing stuff that runs 12V when the ignition is on.

I HATE intermittent electrical issues. In snowmobiles and fourwheelers what you describe is almost always a stator, obviously our trucks don't have stators, but I suspect it is similar cause, when something gets warm (like the stator in ATVs) it causes it to short or otherwise stop electricity from flowing. I would have guessed coil, but you've already checked that. If the coil doesn't have spark I would start tracing back from the coil until I found electricity. If the coil is okay it has to not be getting any juice (or possibly not enough juice) for it not to produce spark.

Ok, so today, I tried to swap the computers again, neither computer will start the other truck for some reason. But I have put all the parts off the truck that isn't working right, on the truck that was running great, and it runs great. It hasn't cut out one single time, and fires up instantly. I have another distributor here that I pulled the pickup coil out of and threw it in the distributor, it fired up for about 14 seconds and died as if I had turned the key off. Still no forward progress.

Looks like you have just about narrowed it down to a wiring harness issue.

You're gonna need to get a 29,95 multimeter and start measuring.

I need to to some myself tomorrow.

Solved
 

Well the wiggle test came through. I last part I swapped again was the igniter/coil. Truck started right up, I started to wiggle wires, first harness I grabbed ahold of was the plugin for the igniter, truck died. I lifted the wiring back up, truck started right up, I push it down, truck dies. It was the Spade in the connector itself, It was only making contact if it was held just right, I tightened up the spade and all is done. I swapped all the original parts back to the truck also and I'm ready to be back on the road again with this thing. Thank you all for the ideas and help.

Thank you for sharing your fix