Diagnostic Procedure
- CHECK EXHAUST SYSTEM
Visually check exhaust tubes and muffler for dent.
OK or NG
- OK : GO TO 2.
- NG : Repair or replace.
- CHECK EXHAUST GAS LEAK
- Start engine and run it at idle.
- Listen for an exhaust gas leak before three way catalyst (manifold).
OK or NG
- OK : GO TO 3.
- NG : Repair or replace.
- CHECK INTAKE AIR LEAK
Listen for an intake air leak after the mass air flow sensor.
OK or NG
- OK : GO TO 4.
- NG : Repair or replace.
- CHECK IGNITION TIMING
- Check the following items. Refer to Basic Inspection .
OK or NG
- OK : GO TO 5.
- NG : Adjust ignition timing.
- CHECK INJECTORS
- Refer to WIRING DIAGRAM for injectors, WIRING DIAGRAM .
- Stop engine and then turn ignition switch ON.
- Check voltage between ECM terminals 102, 104, 109 and 111 and ground with CONSULT-II or tester.
Battery voltage should exist.
OK or NG
- OK : GO TO 6.
- NG : Perform DIAGNOSTIC PROCEDURE .
- CHECK IGNITION SPARK
- Disconnect ignition wire from spark plug.
- Connect a known good spark plug to the ignition wire.
- Place end of spark plug against a suitable ground and crank engine.
- Check for spark.
OK or NG
- OK : GO TO 8.
- NG : GO TO 7.
- CHECK IGNITION WIRES
- Inspect wires for cracks, damage, burned terminals and for improper fit.
- Measure the resistance of wires to their distributor cap terminal.
Move each wire while testing to check for intermittent breaks.
Resistance : 13.6 - 18.4 kΩ/m (4.15 - 5.61 kΩ/ft) at 25°C (77°F)
If the resistance exceeds the above specification, inspect ignition wire to distributor cap connection. Clean connection or replace the ignition wire with a new one.
OK or NG
- OK : Check ignition coil, power transistor and their circuits. Refer to IGNITION SIGNAL .
- NG : Replace.
- CHECK INJECTOR
- Turn ignition switch OFF.
- Remove injector assembly.
Keep fuel hose and all injectors connected to injector gallery.
- Disconnect camshaft position sensor harness connector.
- Turn ignition switch "ON".
Make sure fuel does not drip from injector.
OK or NG
- OK (Does not drip.) : GO TO 9.
- NG (Drips.) : Replace the injector(s) from which fuel is dripping.
- CHECK INTERMITTENT INCIDENT
Perform TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .
- Trouble is fixed: INSPECTION END.
- Trouble is not fixed: Replace three way catalyst (manifold).