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Hard Start Diagnostics🔗

Note

  • Hard start issues occur when the engine cranks but does not start for a long time. Engine may also eventually run or may start but immediately die.
Checks Action
Preliminary Checks Ensure the user is using the correct starting procedure (if applicable).
Sensor Checks - Compare the ECT with the ambient air temperature on a cold start. If the coolant temperature reading is more than 10 degrees greater or less than the ambient air temperature, check for high resistance in the ECT sensor circuit.
- Check the TPS and foot pedal position sensor connections.
Fuel System Checks - Check for intake system leakage.
Ignition System Checks - Check for proper ignition voltage.
- Check the spark plugs are properly gapped.
- Check the spark plugs for any irregular wear, cracks, heavy deposits, and burned electrodes.
Engine Mechanical Checks Check for all of the below items:

- Vacuum leaks
- Improper valve timing
- Low compression
- Improper valve clearance
- Worn or weak valve springs
- Worn camshaft lobes
Exhaust System Checks - Check the exhaust system for any restrictions and damaged pipes