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Backfire Diagnostics🔗

Note

  • Backfire is when the fuel is igniting in the intake manifold, or in the exhaust system, making a loud popping noise.
Checks Action
Preliminary Checks N/A
Ignition System Checks - Check for proper ignition timing
- Check the connection at the ignition coils
- Check the resistance (ohms) of the spark plug wires. If any wires have a reading of over 29,000 ohms, replace those wires.

Remove the plugs and inspect them for any of the below conditions:
- Improper gap
- Any and all deposits
- Wet plugs
- Cracks
- Burned electrodes
Engine Mechanical Checks Check the engine for any of the below conditions:
- Sticking or leaking valves
- Exhaust system leaks
- Improper valve timing
- Engine compression
- Sticking or leaking valves
- Manifold vacuum leaks
Fuel System Checks - Perform a fuel system diagnostics check (Refer to the Fuel System Diagnostics section of the manual).