Code result
P2C79
NOx Adsorber - Sulfur Limit Exceeded
High severity
What it means
The ECM detects that the cumulative sulfur load on the NOx adsorber catalyst exceeds the calibrated threshold. Desulfation regeneration is required to restore catalyst function.
Is it safe to drive?
No — stop driving
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
Operation with high-sulfur fuel
highOne of the most commonly reported causes for this code — check this first.
Desulfation regen strategy disabled or failed
mediumA plausible cause — test and verify before replacing parts.
Related help
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