Codes, sensors & stalling.

Stock '93 5.0. Engine has a bit of trouble starting, then starts, runs for about 10 seconds then stalls. Got codes 21-ECT sensor out of range, 24-ACT sensor out of range, 96 Fuel Pump circuit failure.

I pulled the sensors and checked for resistance as I heated them and they seems fine. I checked the voltage on the sensor wires going into the computer, and they seem to be within range when compared to the table I have (between 0 nd 3.5V).

If I am still getting the codes, but they seem to be sending the right signal to the computer, what is my next step? New sensors, new computer?

I've checked all the grounds and wires in the fuel pump system and can't find anything wrong there either. I can here the fuel pump start when I turn the key and there is pressure in the line, though I haven't measured it.

I cleared the codes after I checked the sensors in case it was a connection or dirt on the sensor but the codes and run problem are still there.

I want to make sure I'm not missing something before I go replacing parts.

Any suggestions? Thanks in advance for any advice.

Garnet

Well 21 and 24 have nothing to do with your stalling problem cause they are not used until the engine is out of open loop. I'd bet on it being a fuel issue. Hook up a pressure gauge to first see if pressure holds when you turn the key to run. Then use it again to see what running pressure is for as long as you can.

Not really sure about the other two. If the sensors are good, the wires are good and all connections are clean, then theres no reason the codes should be thrown again. Hmmm.... Computer is always your last bet, but it can and has happend.

How long does it take for the computer to go to closed loop after the car starts? Is it possible that after running for 10 or 15 seconds it is going to closed loop, and then stalling?

After stalling it doesn't like to start again for a while.

Is there a special gauge to check fuel pressure on these cars?

Thanks for the input.

Garnet

A regular fuel gauge will work. There's a schraeder valve on the fuel line just before it goes up into the injector rails. You connect on that.