Engine Is Difficult to Start

ENGINE IS DIFFICULT TO START

Conditions for Fault Tracing
^ No DTCs present.
^ Engine hot.

Fault sources
^ Contact resistance in Engine Speed (RPM) Sensor connector.
^ Faulty RPM Sensor.
^ Contact resistance in Camshaft Position (CMP) Sensor connector.
^ Leaking Exhaust Gas Recirculation (EGR) Valve.
^ Leaking EGR Controller.
^ Contact resistance in Engine Coolant Temperature (ECT) Sensor connector.
^ Faulty ECT Sensor.
^ Faulty or damaged Spark Plug and/or Ignition Lead.
^ Faulty Distributor Cap and/or Rotor.
^ Incorrect fuel pressure or residual fuel pressure.
^ Contact resistance in Ignition Systems' (DI) Power Stage connector.

TESTING PROCEDURE





Cleaning and Greasing of Control Module Connectors
^ Switch off ignition.
^ Remove both control modules, (MFI and ICM).
Located on the right side of the engine compartment, inside the Control Module Box.

MFI = LH 3.2 Engine Control Module

ICM = EZK 129 Ignition Control Module

^ Check control module connectors for contact resistance and oxidation.
^ Reinstall both control modules.

When connectors have been checked:
- Proceed to: Cleaning and Greasing ECT Sensor Connector.





Cleaning and Greasing of ECT Sensor Connector
^ Switch OFF Ignition.
^ Disconnect sensor.
^ Check sensor connector for contact resistance and oxidation.
^ Reconnect sensor.

When connector has been checked:
- Proceed to: Checking Engine Temperature.





Checking Engine Temperature
^ Switch ON Ignition.
^ Check that value of engine coolant temperature (ECT) is reasonable.

Temperature should be over 75°C (167°F) when engine is hot, upper coolant hose is hot and thermostat is fully open.

If value is correct:
- Proceed to: Cleaning and Greasing CMP Sensor Connector.
If value is incorrect:
- Try with new sensor.
- Proceed to: Cleaning and Greasing CMP Sensor Connector.





Cleaning and Greasing of CMP Sensor Connector
^ Switch OFF Ignition.
^ Disconnect sensor.
^ Check sensor connector for contact resistance and oxidation.
^ Reconnect sensor.

When connector has been checked:
- Proceed to: Cleaning and Greasing RPM Sensor Connector.





Cleaning and Greasing of RPM Sensor Connector
^ Switch OFF Ignition.
^ Disconnect sensor.
^ Check sensor connector for contact resistance and oxidation.

When connector has been checked:
- Proceed to: Checking RPM Sensor.





Checking RPM Sensor
^ Switch OFF Ignition.
^ Disconnect sensor.
^ Connect ohmmeter between sensor connector terminals 1 and 2.

Instrument should indicate 200 - 400 ohms depending on engine temperature.

If reading is correct:
- Proceed to: Cleaning and Greasing DI Power Stage Connector.
If reading is incorrect:
- Try with new sensor.
- Proceed to: Cleaning and Greasing Power Stage Connector.





Cleaning and Greasing of DI Power Stage Connector
^ Switch OFF Ignition.
^ Reconnect RPM sensor.
^ Check power stage connector for contact resistance and oxidation.
^ Reconnect power stage.

When connector has been checked:
- Proceed to: Checking Ignition Coil Primary Winding.





Checking Ignition Coil Primary Winding
^ Switch OFF Ignition.
^ Disconnect one ignition coil lead.
^ Connect ohmmeter between primary winding terminals (1 and 15).

Instrument should indicate 0.5 - 1.5 ohms.

If reading is correct:
- Proceed to: Checking Ignition Coil Secondary Winding.
If reading is incorrect:
- Try with new ignition coil.
- Proceed to: Checking Distributor Cap, Distributor Rotor and Ignition Leads, section below.





Checking Ignition Coil Secondary Winding
^ Switch OFF Ignition.
^ Disconnect coil high-tension lead (king lead).
^ Connect ohmmeter between terminal 15 and high-tension terminal.

Instrument should indicate approx. 8 - 9K ohms.

If reading is correct:
- Proceed to: Checking Distributor Cap, Distributor Rotor and Ignition Leads.
If reading is incorrect:
- Try with new ignition coil.
- Proceed to: Checking of Distributor Cap, Rotor and Ignition Leads.





Checking Distributor Cap, Distributor Rotor and Ignition Leads
^ Switch OFF Ignition.
^ Check distributor cap, distributor rotor and ignition leads for damage, cracks and arcing.

If fault is suspected:
- Clean parts suspected of being damaged / faulty or replace as required.
- Reinstall distributor cap and rotor.
- Proceed to: Checking Spark Plugs.





Checking Spark Plugs
^ Switch OFF Ignition.
^ Replace all spark plugs.
^ Reconnect all ignition leads.

Check Fuel Pressure and Residual Fuel Pressure.
- See: FUEL DELIVERY AND AIR INDUCTION / FUEL PRESSURE / TESTING AND INSPECTION.