Fuel and Emissions Systems Symptom Troubleshooting Index
Symptom Troubleshooting Index

When the vehicle has one of these symptoms, check for a diagnostic trouble code (DTC) with the HDS. If there is no DTC, do the diagnostic procedure for the symptom, in the sequence listed, until you find the cause.

Symptom
Diagnostic procedure
Also check for
Engine will not start
(MIL works OK, no DTCs set)
  
Engine will not start and HDS does not communicate with the PCM
(MIL comes on and stays on, no DTCs set)
PCM power and ground circuit troubleshooting.
  
MIL comes on and stays on, or never comes on at all, no DTCs set
Troubleshoot the MIL circuit.
  
Engine will not start
(MIL works OK, no DTCs set, security indicator stays on or flashes)
Without keyless access system: Check the immobilizer system.
With keyless access system: Check the keyless access system.
  
Engine starts but stalls immediately
(MIL works OK, no DTCs set, security indicator stays on or flashes)
Without keyless access system: Check the immobilizer system.
With keyless access system: Check the keyless access system.
  
Engine is hard to start
(MIL works OK, no DTCs set)
  
Cold fast idle too low
(MIL works OK, no DTCs set)
  
Cold fast idle too high
(MIL works OK, no DTCs set)
Intake air leaks
Idle speed fluctuates
(MIL works OK, no DTCs set)
1.
Do the PCM idle learn procedure.
2.
Check the idle speed.
3.
Check the fuel pressure.
4.
Do the carbon accumulation check.
5.
Troubleshoot the A/C signal circuit.
6.
Check the A/C refrigerant amount.
NOTE: Turning the A/C to ON under the conditions that the A/C refrigerant amount is out of specification (excessive or too little) may cause the idle speed fluctuation.
Incorrect valve adjustment
Intake air leaks
After warming up, idle speed is below specifications without load
(MIL works OK, no DTCs set)
Do the carbon accumulation check.
Incorrect valve timing or clearance adjustment
After warming up, idle speed is above specifications without load
(MIL works OK, no DTCs set)
Inspect the APP sensor.
Intake air leaks
Low power
(MIL works OK, no DTCs set)
Low compression
Incorrect camshaft timing
Incorrect engine oil level
Exhaust restriction
Fuel contamination
Intercooler insufficient cooling (for some models)
Engine stalls
(MIL works OK, no DTCs set)
Troubleshoot the engine stalls.
  
Difficult to refuel
(MIL works OK, NO DTCs set)
1.
Check the fuel vent tube between the EVAP canister and the fuel tank unit.
2.
Check the fuel tank vapor recirculation tube between the fuel fill pipe and the fuel tank unit.
3.
Insert the emergency fuel funnel into the fuel filler neck, then check the operation of the shut-off valve flap.
NOTE: The emergency fuel funnel is stored in the trunk tool box.
4.
Replace the fuel tank.
Malfunctioning gas station filling nozzle
Fuel overflows during refueling
(No DTCs set)
Replace the fuel tank.
Malfunctioning gas station filling nozzle
HDS does not communicate with the PCM or the vehicle
Troubleshoot the DLC circuit.
Correct HDS software