Hi all. I am writing because I have a problem with my truck that stumps my brother and myself. My brother is the mechanic first and foremost. The problem is a little while ago my truck would be going well when driving then for some reason it would cut out and would have trouble restarting. Sometimes while going 60 mph on the highway, it would do this, and sometimes it would do it while turning into my yard or on an on-ramp. This last week it died on me at my doctor's office. Anyways my brother has somewhat narrowed it down to the ASD relay, or the wiring to the PCM, or even the a PCM itself. He is still stumped. The OBD-II has no codes but the test that you can do without a tester comes back with a CODE 42 .

HAVE ANY IDEAS PLEASE LET ME KNOW
THANK YOU IN ADVANCE.

 

42 Fuel pump relay control ckt, Auto shutdown relay control ckt, No ASD relay output voltage at PCM, Fuel level sending unit volts out of range, Fuel level unit No change over miles.

Does the gas gauge work? On the 96, I didn't think the PCM even had a clue about fuel level....

When the truck won't start, do you get power to the coil? Keep in mind, you will only see power there for about 3 seconds at initial key-on, then only if the PCM sees the engine turning....

 

gas gauge does work but you really can not go by that. Ever since I got this truck gas guage would say I am full one minute and empty a few minutes later, to half a tank the next.

 

Either a bad pump module, or a bad connection back there. If the pump itself isn't getting power, the truck certainly won't run... Do you hear the pump prime when it won't start??

 

Yes I hear the pump priming my brother is going to change out the PCM. WE DID however got the thing runn8ng again by him tinkering with it. But to be on the safe side we are changing the PCM.

 

Give it a shot, see what happens..... I think you have more than one problem there though..... I would still be checking the connector back at the pump.