Aron9000

I know there is another thread about three spaces down similar to mine, but mine is acting up in a completely different way . . . .

So its a 93 22RE, 2wd, 5 speed, 170k miles. Truck generally runs awesome, no issues, gets 25mpg. Crank it over, if the coolant is cold, it can be 5 degrees or 105 degrees, it fires right up and settles into the high idle circuit, runs great and warms up to operating temp like it should.

Now the tricky part is if its been running and up to operating temp, I go into a gas station and park it for 5-10 minutes, it once again fires up like it should, settles into low idle, runs exactly like it should.

The main thing is if I go shopping, the engine is warm and been sitting for about 20 mins to about an hour, hour and a half, it will crank over and barely catch. The oil pressure light stays on for a second or two, you hear a nasty sort of thump like its not getting oil circulated everywhere for about a second or two until the light goes out.

After that happens, it idles rough and too low, blip the throttle with the clutch pushed in, it hesistates, then kind of catches itself and revs normally. It will then go back into that crappy low idle that shakes the whole truck.

The weird thing is I've figured out a workaround for that hot start issue, you just push the gas in a little bit(like if you were going to take off from a stop) while you crank it, it fires up immediately, no oil pressure light, no weird noise, settles into the normal low idle, runs like it should.

Any ideas on what's wrong? I'm thinking its some sort of resistor or spring gradually wearing out, as this used to be a random issue, now it does it every time the engine is heat soaked.

EDIT: Other than this random issue, the engine runs great, pulls hard in any gear.

Rerunn

Clean the Tb and look into a thermo time switch.
Mine was acting similar and I replaced the this switch and it improved.