
TROUBLESHOOTING (Cont'd)
Problem | Possible cause | Remedy | Page
Engine hesitates/Poor acceleration | Vacuum leaks
• PCV hoses
• EGR valve
• Intake manifold
• Air intake chamber
• Throttle body
• ISC valve | Repair as necessary |
Pulling in air between air flow meter and throttle body | Repair as necessary | FI-58, 63
Incorrect ignition timing | Reset timing | IG-10
Emission control system problem (cold engine)
• EGR system always on | Check EGR system |
Ignition wiring faulty | Inspect wiring |
Fuel system clogged | Check fuel system | FI-44
Air cleaner clogged | Check air cleaner |
Fuel system problems | Repair as necessary |
Spark plugs faulty | Inspect plugs | IG-5
Engine overheats | Check cooling system | CO-2
Low compression | Check compression | EM-6
Engine diesels (runs after ignition switch is turned off) | EFI system problems | Repair as necessary |
Muffler explosion (after fire) on deceleration only | Deceleration fuel cut system always off | Check EFI (fuel cut) system | FI-79
Muffler explosion (after fire) all the time | Air cleaner clogged | Check air cleaner |
EFI system problem | Repair as necessary |
Incorrect ignition timing | Reset timing | IG-10
Engine backfires | Vacuum leak
• PCV hoses
• EGR valve
• Intake manifold
• Air intake chamber
• Throttle body
• ISC valve | Check hoses and repair as necessary |
Pulling in air between air flow meter and throttle body | Repair as necessary | FI-58, 63
EFI system problem | Repair as necessary |
Insufficient fuel flow | Troubleshoot fuel system |
Incorrect ignition timing | Reset timing | IG-10
Carbon deposits in combustion chambers | Inspect cylinder head | EM-18
Excessive oil consumption | Oil leak | Repair as necessary | LU-4
PCV line clogged | Check PCV system | EC-4
Piston rings worn or damaged | Check rings | EM-38