P2424 code meaning
HC Adsorption Catalyst Efficiency Below Threshold (Bank 2)
Powertrain system Generic code P24xx codes Check engine light
What P2424 means
P2424 applies the same check to the bank 2 hydrocarbon trap, so it can only appear on V or flat engines that have such a trap in each exhaust branch. No manufacturer documents P2424 publicly. The only published case of the family is Nissan's P2423 on the four-cylinder Altima SULEV, which has a single bank; there the trap sits with the front catalyst in the front exhaust tube, and the remedy is replacing that part under an extended emission warranty. CARB leaves the monitoring method for such traps to a plan the manufacturer must have approved, so thresholds are not public. With P2424 the engine runs normally; what suffers is the cold-start hydrocarbon output of the second bank.
P2424 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyHard
- Typical labor1 to 3 hours
- Clears after repairAfter a drive cycle
Symptoms of P2424
- Check engine light
- Possible failed emission inspection
Common causes of P2424
- Most likelyBank 2 adsorber layer aged or contaminated
- PossibleExhaust leak ahead of the bank 2 trap distorting the measurement
- Less likelyThermal damage from misfires on bank 2
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hc adsorber catalyst
What each part of P2424 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 4 | Area: auxiliary emission controls (catalytic converter, EGR, EVAP). |
| 24 | The exact fault in that area. |
What to do next
- Note P2424 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2424
What does P2424 mean?
P2424 means "HC Adsorption Catalyst Efficiency Below Threshold (Bank 2)". P2424 applies the same check to the bank 2 hydrocarbon trap, so it can only appear on V or flat engines that have such a trap in each exhaust branch. It is a generic code, so it means the same on every make.
Is it safe to drive with P2424?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P2424 fail an emissions test?
Yes, it can. P2424 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2424 to fix?
Difficulty: hard. A typical repair takes 1 to 3 hours of work. This is a job for a workshop.
Will P2424 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.