33

Possible Causes

• •Difference in voltage between sensed voltage (pin circuit 17 for metal-cased ECU, pin circuit 2 for plastic-cased ECU) and actual injector voltage (circuit 45/45A)
• •Engine wiring harness pin circuit wiring or connectors issue (Pin 10 for 35 Pin MA 1.7 Metal-Cased ECU, Pin 11 for 24 Pin MSE 1.0 Plastic-Cased ECU, Pin 20 for 32 Pin MSE 1.1 Plastic-Cased ECU)
• •Exhaust leak
• •Fuel inlet screen plugged (in-tank fuel pump only)
• •Fuel system issue (fuel type/quality, injector, fuel pump, fuel pressure)
• •Ignition system issue (spark plug, plug wire, ignition coil)
• •Incorrect fuel pressure at fuel rail
• •Oxygen sensor connector or wiring problem
• •Oxygen sensor contaminated or damaged
• •Poor ground path
• •Restricted return line causing excessive fuel pressure
• •TPS problem or malfunction
• •Throttle plate position incorrectly set or registered during Initialization
• •Uncleared ECU fault codes after problem correction

Suggested Actions

1. 1Disconnect the negative (-) battery cable from battery terminal, or remove the main fuse for the ECU for approximately 1 minute
2. 2Reconnect the cable and tighten securely, or reinstall the main fuse
3. 3Start the engine and allow it to run for several minutes (10-15 minutes of running may be required for codes 31, 32, 33, and 34 to reappear) to verify the MIL remains off

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