Weird running issues.

Hey guys so this is an issue I've been having for several years now. We will start with the vehicle. 1990 D50, 2.4 5 speed, standard cab standard bed.

Recent maintenance:

Timing set
Water pump
Plug/wires
New 02 sensor
New exhaust
Coolant temp sensor
Cleaned MAF, but did not test
There were wiring issues that cause the fuel gauge and turn signals not to work, fixed that

So the truck has a weird idle. When sitting still it is not steads, varies about 300 rpms if my ear tach is calibrated correctly. Just a steady normal idle, down 300 rpms, back to normal, and back down the entire time its sitting.

Then the weirder issue. Sometimes the truck dies randomly. It runs great, but sometimes it will just die. Sometimes it restarts instantly and runs fine, sometimes it has to sit for a couple of days before it will start back up.

Any ideas?

TPS or bad MAF - either will cause the weird idle issue.

Bad capacitors for the random dying issue, that's a common symptom. Search around on the forum for pictures of the leaky caps and burn marks and where to send the ECU to get rebuilt.

Thank you guys for the answers. The bad caps I'm guessing are around the ecu area?

yes just open the cover and look at the board on both sides - look for leaking or bulged capacitors as BradMPH mentioned

Thank you.