DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - PERFORMANCE


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 8 - ELECTRICAL/STARTING - DIAGNOSIS AND TESTING).
  		  
4. Incorrect spark plug gap.
  		 4. (Refer to 8 - ELECTRICAL/IGNITION CONTROL/SPARK PLUG - CLEANING).
  		  
5. Dirt or water in fuel system.
  		 5. Clean system and replace fuel filter.
  		  
6. Faulty fuel pump, relay or wiring.
  		 6. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
 		  
ENGINE STALLS OR ROUGH IDLE
  		 1. Idle speed set to low.
  		 1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
 
2. Vacuum leak.
  		 2. Inspect intake manifold and vacuum hoses, repair or replace as necessary.
  		  
3. Incorrect engine timing.
  		 3. (Refer to 9 - ENGINE/VALVE TIMING - STANDARD PROCEDURE).
  		  
ENGINE LOSS OF POWER
  		 1. Dirty or incorrectly gapped spark plugs.
  		 1. Replace spark plugs.
  
2. Dirt or water in fuel system.
  		 2. Clean system and replace fuel filter.
  		  
3. Blown cylinder head gasket.
  		 3. Replace cylinder head gasket.
  		  
4. Low compression.
  		 4. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
  		  
5. Burned, warped or pitted valves.
  		 5. Replace as necessary.
  		  
6. Plugged or restricted exhaust system.
  		 6. Inspect and replace as necessary.