1990 Ranger 2.9L - trying to keep my Ranger alive

[aemiller]

Yesterday morning, I drove to the lumber yard about two miles from my house. A quarter of a mile from home, the truck started to miss and pop. I limped on to the lumber yard, stalling and starting again a half dozen times. After picking up my lumber (2 pieces) I took the back way home rather than risk stalling on the main road. The truck worked fine. I was scheduled to help a friend about seven miles away. Again the truck worked fine as I drove to his house.

After several hours there, I started the truck to head for home. Again, I was hearing the misses and the popping. I thought I would try to limp home, but after only a hundred yards or so, the truck began missing, popping and stalling repeatedly. I found a place to turn around and headed back to my friend's house. On the way back, a forceful backfire blew out the side of the muffler.

My friend was a mechanic. Using ether we were able to start the truck. He suggested that it might be the fuel filter. I got a new filter and replaced it. We checked the fuel pressure at the Shrader valve on the fuel rail. Yesterday it was holding steady at about 32 psi. The truck started readily but stalled after about ten or fifteen seconds. I quit for the day.

I went back again this morning. I confirmed that the fuel pump is pumping fuel. Today's fuel pressure was steady at 42 psi. Again the engine starts but only lasts about 10 – 15 seconds and abruptly quits. I am not seeing any 'check engine' codes.

This is a project truck. It is not driven hard. (I only had about 1000 miles over the last year.) Last year I did replace the head gaskets, spark plugs, ignition wires, air intake temperature sensor, and MAP sensor.

This was not a gradual failure. It happened over just a few miles. I would greatly appreciate any advice. (I could give up and sell the truck, but I would really like to get this figured out.)

 

[alwaysFlOoReD]

I used to deliberately shut off my car while cruising down main street (small towns and carbs) and then turn it back on after a few seconds. A nice big bang would happen as the hot exhaust gases would hit the unburnt gas in the exhaust system. Eventually blew out the muffler.
I would suspect something wrong with the fuel system. Maybe a fuel injector sticking open?

 

[aemiller]

I used to deliberately shut off my car while cruising down main street (small towns and carbs) and then turn it back on after a few seconds. A nice big bang would happen as the hot exhaust gases would hit the unburnt gas in the exhaust system. Eventually blew out the muffler.
I would suspect something wrong with the fuel system. Maybe a fuel injector sticking open?

Thank you for that response. That may be what is happening. Do you have any advice on how I check for a sticking injector?

 

[alwaysFlOoReD]

If you have your foot to the floor and then turn the engine over there should be absolutely no attempt by the engine to fire up. Foot to the floor while starting tells the computer "clear flooded engine".
If it does try to fire then check spark plugs. The wet one(s) are the cylinders that have injectors leaking.