|
|
Tdi 1 FAULT DIAGNOSIS ENGINE OVERHEATING Before conducting any cooling system diagnosis: See Description and operation, Engine Cooling 1. Is coolant level correct? NO - Allow engine to cool, top up level to YES - Continue. 2. Is drive belt tension correct? NO - See ENGINE, Repair, Compressor Drive Belt YES - Continue. 3. Is coolant in radiator frozen? YES - Slowly thaw and drain system. See Adjustment, Coolant NO - Continue. 4. Is air flow through radiator restricted or blocked? YES - Apply air pressure from engine side of radiator to clear obstruction. NO - Continue. 5. Are there any external leaks, from water pump, engine gaskets, fast idle thermostat or the heater See Adjustment, Coolant NO - Continue. 6. Are fan blades fitted correct way round, concave side towards engine? Rectify. YES - Continue 7. Is viscous unit operating correctly? See Description and operation, Viscous Fan Renew. See Repair, Viscous Coupling, Fan Blades, Pulley and Fan YES - Carry out a pressure test on radiator cap and system. Check thermostat type, See Repair, Thermostat If pressure test leads you to suspect coolant 8. Are the air conditioning fans operating correctly? See Electrical Trouble Shooting Manual. Rectify. YES - Continue. 9. Is temperature sender and gauge giving accurate readings? Sustitute parts and compare readings. YES - Continue. 10. Carry out cylinder pressure test to determine if pressure is leaking into cooling system causing If problem is not diagnosed, check the coolant system If only the coolant system is contaminated suspect a If both systems are contaminated, suspect the If only the lubrication system is contaminated with |