Checks
| Action
|
DEFINITION: Ignition occurs in the intake manifold, or
in the exhaust system, making a loud popping noise.
|
Preliminary
|
|
Sensor/System
| Check the following systems for proper operation:
• | Exhaust gas recirculation (EGR) system |
• | Positive crankcase ventilation (PCV) system |
• | Knock sensor (KS) system |
|
Ignition System
|
• | Check for proper routing of the ignition control (IC) circuits
in each ignition module assembly connector. |
• | Check the ignition coils for signs of carbon tracking or damage. |
• | Check for proper spark plug boot alignment. |
• | Check the spark plugs for proper heat range and reach. |
|
Engine Cooling System
|
• | Check the engine thermostat for proper operation or for the wrong
heat range. Refer to
Thermostat Diagnosis
in Engine Cooling. |
|
Engine Mechanical
|
• | Check the following conditions: |
- | Sticking or leaking valve |
- | Excessive oil in the combustion chamber-leaking valve seals |
• | Check for incorrect basic engine parts. Inspect the following: |
|
Additional Checks
|
• | Inspect the vacuum hoses for splits, kinks, proper routing, proper
connection, and fuel loading. Refer to the Emission Control Information
label. |
• | Check the secondary air injection (AIR) check valves for proper
operation. |
• | Check the exhaust system for possible leaks and/or restrictions. |
|