1993 LWB 4.2L one problem fixed now for the next one. When it gets warmed up rather by just letting it idle or driving it, it begins to stall out, like it's running out of gas, but if you press the gas it will backfire threw the air filter box but stay running. It will do it for about 30sec to 1 min. then the check engine light comes on but it stays running.
The motor seems to be running rough like a it has a miss but can't fugue that out either, because it ran fine till I took it on a test drive a few weeks ago. I put in new 02 sensors, plugs, wires, fuel filter, fuel pump and coil. Checked all the fuel pressure sensor etc. they seem fine.

 

First thing that comes to mind is the MAF sensor. If you disconnect it, it will run on a default program and disregard the MAF sensor readings. Therefore running a tad rough, but normal. It might also be the TPMS. I know you do not have obd II on the classic, but you should get OBD I. It would help if you knew the code it was throwing.

 

It throws a code 44 sometimes now since I put in the new 02 sensors, but I will put the old 02 back and it will still tell me 44 only sometimes. It all started with the catalytic converter heating up put in new 02's it fix that problem, but still running rough, like I said it just started all of a sudden. I will try what you suggested today and see what happens.
Thanks

 

I love code 44... one of the most vague codes there are. I agree with the MAF as a likely cause based on what else you have already replaced or checked, BUT I'd clean it and reconnect it too.

 

I finally got some free time to work on the RR. While it was running I pulled the MAF it did what you said ran rough a still had a miss. I put the MAF back on. While it was running I pulled a Fuel injector wire of a injector and nothing, it didn't change anything. I put that one back on and pulled another wire off it seemed like it made it a little difference as in running a little rougher. I also ran a ohms test on the computer where you jump across I guess to test the injectors. If I did it correctly it said I have 3 injectors bad on one side, it never gave me a reading or anything on the other side. It seems the miss starts about 1-2 minutes after I start it when it's cold. Thanks

 

You could definitely try replacing the injectors, judging on what all else you did, it seems like the last thing to check. I would clean the MAF first, since the spray is cheap anyways. I know this is a "snake oil" solution, but you could try putting some sea foam or injector treatment in the fuel to see if it makes any difference. Who knows, it might work. Another thing you might try, taking the faulty injector(s) out and letting them sit in a cleaning agent such as seafoam for a couple hours.