Engine Starts:
· Fuel Pump secondary circuit shorted to power
· Fuel pump relay contacts always closed
· Open in fuel pump monitor (FPM) circuit between ECU and connection to POWER TO PUMP circuit
· Heated Exhaust Gas Oxygen (HEGO) sensor shorted to power
· faulty ECU
Engine Does Not Start:
· Open inertia switch or inertia switch circuit
· Open in or between ECU and fuel pump (This includes open in fuel pump brushes/windings)
· faulty ground connection at fuel pump
The easiest way to check this circuit is to go to the fuel pump relay. If the relay clicks when the key is turned to the "RUN" position, then the inertia switch circuit is ok.
The Pink/Black wire starts from the fuel pump relay and goes two directions. One side goes back to the fuel pump. The other side is the fuel pump monitor circuit and goes to pin #8 at the ECU. This wire should only be hot for a second or two when the ignition is turned to the RUN position.
The fuel pump relay receives power on the Black/yellow wire. It comes from a fusible link at the power distribution center. This wire should be hot at all times.
If all the above is working as designed, them you probably have a bad fuel pump.
296 views
Usually answered in minutes!
×