Code result
P2A9D
Alternative Fuel High Pressure System Small Leak
Moderate severity
What it means
The AFCM detects a small leak in the high-pressure alternative fuel system based on pressure decay rate after engine shutdown. Common in CNG vehicles where seal aging causes slow gas loss.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Seal aged at fitting or valve
highOne of the most commonly reported causes for this code — check this first.
High-pressure fitting loose
mediumA plausible cause — test and verify before replacing parts.
Related help
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