Diagnostic Procedures
WARNING: This page is about a different car, the 2003 Pontiac Vibe. However, it is still accessible from the selected car via links, so may be relevant.
- Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, perform diagnostic system check - engine controls. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 1.8L VIBE article.
- Connect scan tool. Check engine coolant temperature. Is the engine coolant temperature 50-95°F (10-35°C)? If yes, go to next step. If no, go to FUEL INJECTOR COIL TEST - ENGINE COOLANT TEMPERATURE OUTSIDE 50-95°F (10-35°C) .
- Turn ignition switch to OFF position. Relieve fuel pressure. See FUEL SYSTEM PRESSURE RELEASE
. Connect the Fuel Injector Tester (J 39021), or equivalent, to battery voltage and ground. Set the amperage supply selector switch on the fuel injector tester to the COIL TEST 0.5 AMP position. Connect leads from a DMM to the fuel injector tester. See Figure
. Set DMM to the tenths scale (0.0). Disconnect fuel injector harness connector. Using 2 jumper wires from the Connector Test Adapter Kit (J 35616-A), or equivalent, connect the fuel injector to the J 39021 tester leads.
Check the engine coolant temperature again to ensure that the correct chart is being used. Press the PUSH TO START TEST button on the fuel injector tester. Observe the voltage reading on the DMM. The voltage reading may rise during the test. Record the lowest voltage observed after the first second of the test. Repeat procedure for each fuel injector. Did any fuel injector have an erratic voltage reading or a voltage reading outside of 6.7-7.7 volts? If yes, go to next step. If no, go to FUEL INJECTOR BALANCE TEST WITH SPECIAL TOOL .
- Replace the faulty fuel injectors. After repair, go to FUEL INJECTOR BALANCE TEST WITH SPECIAL TOOL .
WARNING:
Wrap a shop towel around the fuel pressure connection to reduce the risk of fire and personal injury. The towel will absorb any fuel leakage that occurs during the connection of the fuel pressure gauge. Place the towel in an approved container when the connection of the fuel pressure gauge is complete.
CAUTION:
To prevent flooding of a single cylinder and possible engine damage, relieve the fuel pressure before performing the fuel injector coil test procedure.