Repair 7

How to Troubleshoot a Fuel Pump for a 1989 Chevy Truck

A 1989 Chevrolet truck may be an S-10 or a member of the C/K series. The S-10 is a compact pickup truck, and the C/K series are full-size pickup trucks. These vehicles generally use an early form of fuel injection called throttle body injection. This type of fuel requires a low-pressure fuel pump that delivers fuel in the range of 9 to 13 pounds per square inch. A malfunctioning fuel pump typically requires you to replace the fuel pump.

Instructions

1

Loosen the fuel filler cap and remove the fuse for the fuel pump in the fuse box of the passenger compartment. Start the engine and allow it to stall. Crank the engine for three seconds and turn the ignition off. Replace the fuse for the fuel pump. Open the hood and disconnect the cable from the negative terminal on the battery with a socket wrench.

2

Siphon the fuel through the filler tube to drain the fuel tank into a gasoline-approved container. Raise the rear of the truck with the jack. Place jack stands under the frame and lower the vehicle onto the stands. Loosen the retaining clamp for the filler hose on the fuel tank, and disconnect the filler hose. Disconnect the fuel and vapor lines from the fuel tank, and disconnect the fuel hoses and electrical wiring from the fuel tank. Raise the jack to support the fuel tank, and remove the straps on the fuel tank. Lower the fuel tank slightly to gain access to the fuel sending unit. Disconnect the fuel lines and electrical wiring from the fuel sending unit. Lower the fuel tank to the ground.

3

Turn the cam locking ring on the fuel sending unit counterclockwise with tool No. J-24187 or J-36608. Remove the cam locking ring, and disconnect the fuel sending unit from the fuel tank. Discard the old gasket on the fuel tank. Pull the fuel pump from the bottom support and into the mounting tube without damaging the insulator or the fuel strainer. Pull the fuel pump out of its rubber connector.

4

Push the new fuel pump into the mounting tube of the fuel sending unit, and place the new gasket onto the fuel tank. Lower the fuel sending unit into the fuel tank without folding the fuel strainer.

5

Attach the cam locking ring on the fuel sending unit. Turn the locking ring clockwise with tool No. J-24187 or J-36608 until the locking ring locks into place. Connect the fuel tank and fill it with fuel. Connect the cable for the negative battery terminal, and check the fuel system for leaks.