Injectors

Injector repair or overhaul must be performed at a diesel workshop. Never attempt this work yourself. In addition to requiring special tools, injection pressure can cause serious injury if fingers are placed near the injection spray. To identify a malfunctioning injector, loosen the injection pipes from the injectors one at a time and run the engine. If engine operation does not change after loosening the pipe from a particular injector, that injector is faulty.

Removal and installation

PROCEDURE
1. Loosen both nuts securing the injection pipes to the intake manifold. Loosen both union nuts of each injection pipe with a flare nut wrench. This wrench can be fitted onto the nut when the pipe is in place; otherwise use a standard wrench. Loosen the clamps and remove the pipes.
2. Disconnect the fuel hose from the leak-off pipe, remove the four nuts, and remove the leak-off (return) pipe and washers.
3. Remove the injectors using an extension wrench. Toyota service stations use a special tool for this. Do not damage the injectors. Keep the injectors in removal order if they will be reinstalled.
4. Install the injectors in reverse order.
5. Always replace the sealing washers when installing. Injector tightening torque is 65 N·m. Do not exceed this torque, as the injectors may bend or the injector needles may seize.
6. Install four washers on the injectors and connect the return pipe. Install the four nuts and tighten them to 30 N·m. Connect the hose to the return pipe.
7. Install the injection pipes. First, loosely secure both clamps on the intake manifold and start all union nuts of the pipes by hand. Tighten the union nuts to 30 N·m; do not overtighten. Then secure the pipes with both clamps and nuts.
8. Crank the engine with the starter and loosen the union nuts on the injector side one at a time to bleed the air. Retighten the union nuts to 30 N·m.
9. Perform the remaining work in reverse order.