Backfires

Fuel ignites in the intake manifold, or in exhaust system, making a loud popping noise.

POSSIBLE CAUSE ACTION

EGR open all the time,
leaking gasket 1. Check EGR system.
If OK, proceed to step 2
2. Check EGR electronic controls.



Air management valves,
Deceleration valve,
Check valves malfunctioning Check Air Injection system (if equipped)