Range Rover 3.5 Litre (non cat) diagnostic checklist symptom 1
POOR OR ROUGH IDLE - vehicle can be OK for short while following service or tune up (vehicle does not retain CO setting - CO goes high/very rich).
1a. Carry out hydrocarbons dye test on coolant (identifies head gasket problems). This test should be carried out out whenever there are idling or running problems with Rover V8 engines.
1b. Physically check throttle sensor rotation (should be smooth). Check output voltage at idle - should be between .3V and .36V. Adjust if necessary.
1c. ALWAYS REPLACE water temperature sensor. (the one behind the easy one!)
1d. Check for sticking/rough airflow meter flap operation.
1e. Ignition advance timing and spark OK?
1f. If above check out OK then ECU is faulty.
Back to Range Rover 3.5 Litre symptoms