Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the special filter in your car that helps clean the air has too much sulfur in it, which can make it not work properly.
The NOx adsorber is a part of the exhaust system that reduces harmful nitrogen oxides. When it gets too much sulfur, it can't work as well.
The NOx adsorber is designed to trap nitrogen oxides (NOx) from the exhaust gases. Sulfur in the fuel can poison the adsorber, reducing its efficiency. This code indicates that the sulfur content has exceeded the threshold, impairing the adsorber's function.
• Check Engine Light is on
• Increased emissions
• Reduced fuel efficiency
• Use of high-sulfur fuel
• Faulty NOx adsorber
• Exhaust leaks
NOx: Nitrogen Oxides, pollutants that contribute to smog and acid rain.
Adsorber: A device that captures and holds substances from a gas or liquid.
• Check for any exhaust leaks.
• Inspect the NOx adsorber for damage.
• Analyze the fuel sulfur content.
• Replace the NOx adsorber if damaged.
• Use low-sulfur fuel.
• Repair any exhaust leaks.
• OBD-II scanner
• Wrench set
• Fuel sulfur content tester
$300 - $1,200
Moderate
• Chevrolet Cruze
• Volkswagen Jetta
• BMW 3 Series
• Use low-sulfur fuel.
• Regularly inspect the exhaust system.
• Follow manufacturer maintenance schedules.
Emission Control Issue
• Use quality fuel to prevent sulfur buildup.
• Schedule regular maintenance checks.
Check with the manufacturer for emission system warranty coverage.
This code has become more common with the introduction of stricter emission standards and the use of diesel engines.
Moderate – Addressing this issue helps maintain vehicle performance and emissions compliance.
Driving with this code may lead to increased emissions, which can be illegal in some areas.
• Engine at operating temperature
• Vehicle driven under normal conditions
The NOx adsorber is located in the exhaust system, typically near the catalytic converter.
Q: Can I drive with a P2C79 code?
A: It's possible, but it's not recommended as it can lead to higher emissions and reduced performance.
Q: How do I know if my fuel has too much sulfur?
A: Check the fuel specifications at the pump or consult with your fuel supplier.
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