GENERAL 2-11 TROUBLESHOOTING Symptom Possible cause Remedy Low compression Cylinder head gasket damaged Worn or damaged piston ring Worn piston or cylinder Worn or damaged valve seat Replace gasket Replace ring Repair or replace piston and cylinder block Repair or replace valve and seat ring Low oil pressure Insufficient engine oil Oil pressure switch defective Oil filter clogged Worn oil pump gear or cover Thin or diluted engine oil Oil relief valve clogged(Open) Excessive bearing clearance Check engine oil level Replace oil pressure switch Install new filter Replace Replace engine oil Replace or inspect Replace bearing High oil pressure Oil relief valve clogged(Closed) Repair relief valve Noisy valve Thin or diluted engine oil Faulty HLA Worn belt stem or valve guide Replace engine oil Replace HLA Replace belt stem or valve guide Noisy connecting rod or timing belt Insufficient engine oil Low oil pressure Thin or diluted engine oil Excessive bearing clearance Check engine oil level Refer to too low oil pressure Replace engine oil Replace bearing Noisy timing belt Incorrect belt tension Correct belt tension Low coolant level Coolant leak from Heater or radiator hose Defective radiator cap Thermostat housing Radiator Water pump Repair or replace parts Retighten clamp or replace Replace gasket or housing Replace Replace parts Radiator clogged Foreign material into coolant Replace coolant Abnormally high cool- ant temperature Thermostat defective Radiator cap defective Abnormal flow in cooling system Loose or missing driving belt Loose water pump Water temperature wiring defective Cooling pan defective Radiator or thermostat switch defective Inefficient coolant Replace parts Replace parts Clean or replace parts Correct or replace Replace Repair or replace Repair or replace Replace Add coolant