Manager Forum

the truck has two tanks. both senders are good, instrument cluster good,relay for pump good. some times it works then it stops working at anytime.when it stops there is no power to pump or senders. there is no fuses blown and cleaned all grounds. any suggestion would be helpful thanks.

i believe there is a module on the drivers side frame under the drivers seat area.

did not find one

just a quick question here, are there any other systems that seem to fail such as radio, heater, etc.? there were issues with the dash clusters on some of these trucks. usually the brake and a.b.s. light would light up as well. there is a balancing module on this truck. i thought it was on the frame under the drivers seat. the module reads the fuel in the front tank and transfers fuel from the rear as needed. the rear sender is read only by the module. the gas gauge is controlled by the front sender. if you are loosing the gauge and fuel pressure look closely at the connectors. i'm not sure is this was one of the vehicles where the harness would melt. i've also had issues in the harness as it crosses along the transmission support. from time to time i run into issues where some jack a** has punctured the harness with a probe. these types of failures usually will not be intermittent. the faulty plugs will be. i'm not sure if the gauge and the pump fails at the same time with the connector on the mount frame but i would look carefully at it.

Take a look at the bottom of the engine room fuse block...known for mice making nests and chewing wires under there. Had quite a few with strange issues that were caused by this.

did not find module, but customer took truck and it went into limp mode.

then would not restart; has codes po463, po621, p1093, p1094, p2066, p2068. have to keep priming, not finding any holes or loose lines.

looks like possible pcm....................................

truck will start with a small shot of starter fluid and run good.but my fuel rail pressure regulator fuel flow with scanner reads 7400 mm3, should be 12000mm3

i'm not sure here but that may be a direct result from limp.

now when it starts only code i get is 1094. iam leaning towards injections pump