Fuel Injectors (Turbo)
- Start engine and allow engine to idle. Using stethoscope, check for fuel injector operating sound. Fuel injector operating sound should be heard. If fuel injector operating sound is not heard, defective wiring circuit may exist between fuel injector and Engine Control Module (ECM). The ECM is located below passenger's side of instrument panel, underneath carpet on the floor. If necessary to check wiring circuit, see appropriate wiring diagram in WIRING DIAGRAMS article.
- Ensure ignition is off. Disconnect electrical connector at fuel injector. Using ohmmeter, check resistance between electrical terminals on fuel injector. Replace fuel injector if resistance is not within specification. See FUEL INJECTOR RESISTANCE table.
- To check fuel injector volume, remove fuel injector. See appropriate REMOVE/INSTALL/OVERHAUL article. Using NEW insulator, reinstall fuel injector on delivery pipe (if removed).
- Disconnect fuel inlet hose from end of fuel filter. Using Unions (09405-09015) and delivery hose from Fuel Injector Measuring Kit (09268-41046), install delivery hose between fuel filter and delivery pipe. See Fig 1-39. Tighten union bolts to 22 ft. lbs. (30 N.m).
- Using Union (SST 09268-41071), connect return hose to fuel pressure regulator. See Fig 1-39.
- Place fuel injector into a clean graduated container. Place vinyl tube on end of fuel injector to prevent fuel spillage.
- Connect scan tool to data link connector No. 3. See Fig 3. Turn ignition on. DO NOT
start engine. Turn scan tool on. Select ACTIVE TEST MODE on scan tool. Using scan tool manufacturer's instructions, activate fuel pump.NOTE: Fuel pump may also be operated to pressurize fuel system by applying battery voltage to electrical terminals on fuel pump. For operating of fuel pump, see FUEL PUMP RESISTANCE & OPERATION under FUEL DELIVERY under FUEL SYSTEM.
- Connect Fuel Injector Tester (09842-30060) to fuel injector for 15 seconds. See Fig 4.
- Measure fuel injector volume. Test each fuel injector 2-3 times. Replace fuel injector if fuel injector volume is not within specification. See FUEL INJECTOR VOLUME SPECIFICATIONS table.NOTE: Ensure difference between fuel injector volume on all fuel injectors is within specification. See FUEL INJECTOR VOLUME SPECIFICATIONS table.
- Disconnect fuel injector tester. Ensure fuel leakage from end of fuel injector does not exceed one drop in 3 minutes. Replace fuel injector if leakage exceeds specification. Remove test equipment. Using NEW gaskets, reinstall fuel inlet hose on fuel filter. Tighten union bolt to 22 ft. lbs. (30 N.m).
FUEL INJECTOR RESISTANCE
| Application | Ohms @ 68°F (20°C) |
|---|---|
| Non-Turbo | 13.4-14.2 |
| Turbo | 1.95 |
FUEL INJECTOR VOLUME SPECIFICATIONS
| Application | Cu. In. (cc) | |
|---|---|---|
| Volume | ||
| Non-Turbo | 3.7-4.5 (60-73) | |
| Turbo | 7.1-8.4 (116-137) | |
| Maximum Difference Between Each Fuel Injector | ||
| Non-Turbo | .8 (13) | |
| Turbo | .6 (10) | |