Repair 7

How to Replace the Injectors on a 3VZ

The VZ family of engines ers to six-cylinder engines with overhead camshafts that Toyota has manufactured since 1999. The 3VZ engine has a displacement of 3.0 liters and appeared in Toyota trucks from 1988 until 1995. This engine has electronic fuel injectors to deliver pressurized fuel to each cylinder in the correct sequence. The procedure for replacing the fuel injectors on a 3VZ engine is similar for all Toyota trucks.

Instructions

1

Disconnect the cable from the negative battery terminal with a socket wrench. Wrap a shop towel around the banjo bolt on the fuel rail. Loosen the bolt slowly to relieve the pressure in the fuel rail. Tighten the banjo bolt.

2

Position a drain pan under the drain plug for the radiator. Remove the plug with a socket wrench and allow the coolant to drain into the pan. Replace the drain plug.

3

Disconnect the cables to the throttle and accelerator with a socket wrench. Detach the air intake duct. Remove the main wiring harness for the engine and move it out of the way. Disconnect any additional wires and hoses needed to access the fuel injectors in your vehicle.

4

Detach the electrical connectors from the fuel injectors. Release the clamps that attach the wiring harness to the fuel pipe, and remove the wiring harness. Remove the fuel rail and fuel injectors from the intake manifold as an assembly. Remove and discard the insulators and O-rings for the fuel injector.

5

Remove the hose from the bi-metal vacuum switching valve. Disconnect the bolts from the number two and number three fuel pipes with a socket wrench, and detach the fuel injectors from the fuel rail.

6

Insert a new insulator into the injector bore on the intake manifold. Place a new O-ring onto the nozzle end of the fuel injector, and coat the O-ring with a thin layer of gasoline. Press the fuel injector firmly to mount it squarely to the fuel rail.

7

Connect the fuel rail to the intake manifold, and tighten the mounting bolts to between 11 and 15 ft. lbs. with a torque wrench. Ensure the fuel injectors turn freely. Attach the the wiring harness to the fuel rail and plug the electrical connectors into the fuel injectors.

8

Connect any additional wires and hoses that you removed in step 3. Install the air intake duct and throttle body with a socket wrench. Fill the radiator with coolant and attach the cable to the negative battery terminal. Start the engine and check for fuel and coolant leaks.