ECU_Pirate

iTrader: (5)

1998 LS1 car has an SES light on due to no 5 volt reference to the Throttle Position Sensor and EVAP system. In wiring diagrams it shows these two share that 5 volt reference. Oddly enough this all started after the new fuel pump and 9in rear install which makes it hard to swallow that the ECM is shot. Any thoughts?

chrysler kid

iTrader: (14)

Those two wouldn't tell me the ecu is bad. Check the connections they are both on the drivers side

ND2RACE

Did you happen to mess with the wiring under the rear of the car, ie EVAP stuff is right by the rear end. Not sure of your specific DTC, but more often then not that circuit is simply shorted out somewhere, whether wiring or a component. Hope this helps a little, best of luck.

ND2RACE

Did you happen to mess with the wiring under the rear of the car, ie EVAP stuff is right by the rear end, however I think what you mean is the fuel tank pressure sensor which looks like a MAP sensor on top of your fuel sending unit. Not sure of your specific DTC, but more often then not that circuit is simply shorted out somewhere, whether wiring or a component. Hope this helps a little, best of luck.

ECU_Pirate

iTrader: (5)

Checked the ohms of that harness and the negative wire to the tank pressure sensor was at 5...I think I know what to follow... Haha