DIAGNOSTIC TROUBLESHOOTING
6-3
6
Engine surges or misses. Fouled spark plug(s). Check spark plugs. (See “Spark Plugs” on
page 7-8.)
Faulty ignition coil. Check ignition coils. (See “Ignition Coils”
on page 7-8.)
Faulty fuel injector. Check fuel injectors. (See “Injectors” on
page 7-9.)
Valve clearance adjustment. Check valve clearance. (See “Valve
Clearance Check and Adjustment” on
page 5-3.)
Vacuum leak. Check intake manifold vacuum. (See
“Intake Manifold Vacuum Test” on
page 5-2.)
Poor throttle response. Fouled spark plug(s). Check spark plugs. (See “Spark Plugs” on
page 7-8.)
Faulty ignition coil. Check ignition coils. (See “Ignition Coils”
on page 7-8.)
Faulty fuel injector. Check fuel injectors. (See “Injectors” on
page 7-9.)
Valve clearance adjustment. Check valve clearance. (See “Valve
Clearance Check and Adjustment” on
page 5-3.)
Vacuum leak. Check intake manifold vacuum. (See
“Intake Manifold Vacuum Test” on
page 5-2.)
Throttle body gasket leaking air. Check throttle body and gasket. (See
“Throttle Body” on page 7-4.)
Faulty throttle position sensor. Check throttle position sensor. (See
“Throttle Position Sensor” on page 7-3.)
Incorrect fuel. Use proper fuel.
Engine overheats. Coolant level low. Check coolant level.
Water pump belt loose. Check belt tension.
Faulty thermostat. Check thermostat. (See “Thermostat Test”
on page 5-3.)
Faulty water pump. Check water pump. (See “Water Pump” on
page 7-10.)
Faulty head gasket. Check cylinder head and gasket. (See
“Cylinder Head” on page 7-24.)
Condition Probable Cause Remedy