Diagnosis And Testing: Performance

PERFORMANCE CONDITION

CONDITION	POSSIBLE CAUSE	CORRECTION
ENGINE WILL NOT START	1. Weak battery	1. Charge or replace as necessary.
	2. Corroded or loose battery connections.	2. Clean and tighten battery connections. Apply a coat of light mineral grease to the terminals.
	3. Faulty starter.	3. Refer to DIAGNOSIS AND TESTING .
	4. Faulty coil or control unit.	4. Refer to Ignition Coil REMOVAL .
	5. Incorrect spark plug gap.	1. Correct as necessary.
	6. Dirt or water in fuel system.	6. Clean system and replace fuel filter.
	7. Faulty fuel pump, relay or wiring.	7. Repair or replace as necessary.
ENGINE STALLS OR ROUGH IDLE	1. Dirty or incorrectly gapped spark plugs.	1. Correct as necessary.
	2. Idle mixture too lean or too rich.	2. Refer to appropriate Powertrain Diagnosis Information.
	3. Vacuum leak.	3. Inspect intake manifold and vacuum hoses, repair or replace as necessary.
	4. Faulty coil.	4. Refer to Ignition Coil REMOVAL .
	5. Incorrect engine timing.	5. Refer to VALVE TIMING .
ENGINE LOSS OF POWER	1. Dirty or incorrectly gapped spark plugs.	1. Correct as necessary.
	2. Dirt or water in fuel system.	2. Clean system and replace fuel filter.
	3. Faulty fuel pump.	3. Refer to the Appropriate Diagnostic Information
	4. Blown cylinder head gasket.	4. Replace cylinder head gasket.
	5. Low compression.	5. Refer to CYLINDER COMPRESSION PRESSURE .
	6. Burned, warped or pitted valves.	6. Replace as necessary.
	7. Plugged or restricted exhaust system.	7. Inspect and replace as necessary.
	8. Faulty coil.	8. Refer to Ignition Coil REMOVAL .
ENGINE MISSES ON ACCELERATION	1. Spark plugs dirty or incorrectly gapped.	1. Correct as necessary.
	2. Dirt in fuel system.	2. Clean fuel system.
	3. Burned, warped or pitted valves.	3. Replace as necessary.
	4. Faulty coil.	4. Refer to Ignition Coil REMOVAL .
ENGINE MISSES AT HIGH SPEED	1. Spark plugs dirty or incorrectly gapped.	1. Correct as necessary.
	2. Faulty coil.	2. Refer to Ignition Coil REMOVAL .
	3. Dirt or water in fuel system.	3. Clean system and replace fuel filter.