Engine Backfires
WARNING: This page is about a different car, the 1996 Pontiac Firefly and 1996 Geo Metro. However, it is still accessible from the selected car via links, so may be relevant.
If fuel ignites in intake manifold or exhaust system and makes a loud popping noise, check the following items:
- Perform VISUAL/PHYSICAL INSPECTION .
- Ensure sufficient secondary spark is available.
- Ensure ignition timing and controls are working properly.
- Check for faulty spark plugs, spark plug wires, distributor cap and rotor causing crossfire between spark plugs.
- Check for proper spark plug wire routing.
- Check for low compression (sticking or leaking valves).
- Ensure valve timing is correct.
- Check fuel pressure.
- Check EGR (open all the time) and solenoid operation.
- Check intake and exhaust manifolds for casting flash.
- Check exhaust system for leaks.