Fuel Pump - Noise/Chattering/Engine Stalling
19-22Fuel Pump Noise and Hot Weather Engine Stalling - Fuel Pump Cavitation - Install Twin Pumps
MODEL:
88-90 MY Sedans
DATE:
6/93
ISSUE:
Fuel pump noise (chattering) and/or the engine stalling in hot weather can be caused by fuel vaporization at the pump inlet.
If stalling occurs, the engine will start and run normally after a cool down period.
ACTION:
If the above conditions exist, twin fuel pumps can be installed using the following procedure:
CAUTION:
Liquid fuel and fuel vapor will be present during the following procedure. Be sure that the work area is well ventilated. Use precautions to prevent the possibility of explosion and fire.
^ Depressurize the fuel system by starting the engine and removing the fuel pump relay. Run engine until it stalls.
^ Take note of radio stations in memory including X-MEM.
^ Disconnect the vehicle battery.
^ Empty the fuel tank through the filler neck using a portable gas buggy and pump.
^ Raise the vehicle on a lift. Remove both rear wheels.
^ Pinch off the fuel feed hose (from tank to pump).
^ Cut the plastic straps that hold the fuel hoses to the rear subframe.
^ With a fuel waste container nearby, loosen the hose clamp at the connection to the pump inlet. Wrap a shop rag around the connection and carefully remove the hose from pump. Release the pinch clamp and drain the remaining fuel into the waste container.
^ Reinstall the pinch clamp and clean up any spilled fuel.
^ Disconnect the outlet hose and wire leads from the existing fuel pump.
^ Remove the existing fuel pump from the bracket and save for reuse. Leave bracket attached to subframe.
^ Install a new fuel pump (CBC 5656) in the original location. Connect the fuel pump wires and new link lead (DBC 5595) to the pump terminals (blue/red to +, black to -). Fit and tighten pump outlet hose.
^ Align drill template with the front edge of the rear subframe. Align the large hole in template with the hole in the right side crossmember. Tape template in place.
^ Drill two 9/32" holes where indicated on the template. Deburr holes, top and bottom and paint.
^ Fit rubber cushion (CBC 1489) to the right side fuel pump bracket (CBC 8400). Fit the original pump to the bracket with pump inlet to the right. Install but do not tighten the clamp bolt.
^ Install the right side fuel pump and bracket through drilled holes in the subframe and secure with 6 mm washers and Nyloc nuts.
^ Position fuel pump motor terminals to approximately 2 o'clock and 8 o'clock. Tighten clamp bolt.
^ Route the fuel pump link lead across the rear subframe and connect to the right side pump terminals.
NOTE:
The fuel pumps must be wired in parallel; terminal. must be (+) to (+) and (-) to (-).
^ Remove the existing hose from fuel tank to pump. Remove the insulating sleeve and discard hose. Shorten the insulating sleeve to 23-1/2" in length.
^ Slide the shortened sleeve over new fuel feed hose (EBC 10465) and route the hose as indicated in Fig. 1.
^ Check that the two "O" rings are in place on the hose end fitting and install the hose into the fuel tank. Engage the retaining clip on the fuel tank with the groove in the hose fitting. Make sure the hose is secured in the tank.
^ Install the hose clamp and hose onto the right side pump inlet and tighten the hose clamp.
^ Route the branched hose assembly (EBC 10394) from right to left fuel pump as indicated in Fig. 1. Install fitting at right pump outlet and tighten.
^ Install hose clamp and hose onto the left pump inlet and tighten clamp.
^ Pinch off the fuel return hose (from metal pipe to tank). Disconnect the hose at the metal pipe. Remove and discard Viton seal.
^ Route branched hose assembly to the metal return pipe as indicated in Fig. 1.
^ Fit new Viton seal (CBC 4720) to the metal pipe. Connect branch hose adaptor and tighten the fitting.
^ Make sure that a new Viton seal is fitted to the branch adaptor outlet. Connect the return hose and tighten fitting. Release the pinch clamp.
^ Strap hoses and fuel pump link harness to the subframe as indicated in Fig. 1.
^ Check all hose connections and clamps for tightness.
^ Check installation for clearance to moving suspension components and exhaust system. Adjust as necessary.
^ Lower the vehicle and refill fuel tank.
^ Connect the battery.
^ Switch ignition on, wait one second, then switch ignition off. Repeat twice.
^ Raise the vehicle and check connections for fuel leaks. Repair any leaks.
^ Install both rear wheels. Torque lug nuts to 65 ft.lbs.
^ Re-code radio, enter all AM and FM stations into memory and reset clock.
^ Lower the vehicle and roadtest.
PARTS INFORMATION:
WARRANTY INFORMATION: