P2423 Code - HC Adsorption Catalyst Efficiency Below Threshold Bank 1
Quick Answer
The Engine Control Module (ECM) monitors the phase gap between the heated oxygen sensor 2 signal and the heated oxygen sensor 3 signal. Common causes include Hydro Carbon (HC) adsorption catalyst (under floor), Exhaust tube, Intake air leaks. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P2423 indicates HC Adsorption Catalyst Efficiency Below Threshold Bank 1.
- Common causes
- Common causes include Hydro Carbon (HC) adsorption catalyst (under floor), Exhaust tube, Intake air leaks.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P2423 Description
The phase gap between the heated oxygen sensor 2 signal and the heated oxygen sensor 3 signal becomes small as the Hydrocarbon (HC) adsorption catalyst (underfloor) deteriorates.
When the phase gap between the heated oxygen sensor 2 signal and the heated oxygen sensor 3 signal approaches a specified limit value, the HC adsorption catalyst (underfloor) malfunction is diagnosed.
What are the Possible Causes of the DTC P2423?
- Hydro Carbon (HC) adsorption catalyst (under floor)
- Exhaust tube
- Intake air leaks
- Faulty Fuel injector
- Fuel injector leaks
- Faulty Spark plug
- Improper ignition timing
How to Fix the DTC P2423?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P2423 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
Need more information about the P2423 code?
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Need Help with the Code?
Get the P2423 code diagnosed by a professional: Find a repair shop in your area
Information for Specific Makes
- P2423 Dodge — HC Adsorption Catalyst Efficiency Below Threshold Bank 1
- P2423 Infiniti — HC Adsorption Catalyst Efficiency Below Threshold Bank 1
- P2423 Lexus — HC Adsorption Catalyst Efficiency Below Threshold Bank 1
- P2423 Nissan — HC Adsorption Catalyst Efficiency Below Threshold Bank 1
- P2423 Scion — HC Adsorption Catalyst Efficiency Below Threshold Bank 1
- P2423 Toyota — HC Adsorption Catalyst Efficiency Below Threshold Bank 1
Frequently Asked Questions about P2423 Code
1. What does the OBDII code P2423 mean?
P2423 indicates that the HC (hydrocarbon) adsorption catalyst in Bank 1 is not functioning efficiently, as detected by the vehicle’s powertrain control module (PCM).
2. What are the common symptoms of code P2423?
Common symptoms include an illuminated check engine light, reduced fuel efficiency, failed emissions tests, and sometimes poor engine performance.
3. What causes the P2423 code to appear?
Possible causes include a damaged or failing HC adsorption catalyst, a faulty oxygen sensor, exhaust leaks, or engine misfires.
4. Can a faulty oxygen sensor trigger code P2423?
Yes, a malfunctioning oxygen sensor can send incorrect data to the PCM, causing it to misinterpret the catalyst's efficiency.
5. How is P2423 diagnosed?
A mechanic will use an OBDII scanner to retrieve the code, inspect the oxygen sensors, check for exhaust leaks, and test the efficiency of the HC adsorption catalyst.
6. Can I drive my car with a P2423 code?
Driving with this code is possible but not recommended, as it may lead to increased emissions, reduced fuel efficiency, and potential damage to other parts of the exhaust system.
7. What repairs can fix the P2423 code?
Repairs may include replacing the HC adsorption catalyst, repairing exhaust leaks, replacing a faulty oxygen sensor, or addressing any underlying engine issues.
8. How much does it cost to fix a P2423 code?
The cost varies depending on the cause, with oxygen sensor replacement typically costing $150–$350, while HC catalyst repairs or replacements can cost $1,000 or more.
9. Can a clogged catalyst cause P2423?
Yes, a clogged HC adsorption catalyst can reduce its efficiency and trigger the P2423 code.
10. Will clearing the code fix the problem?
Clearing the code will reset the check engine light temporarily, but it will likely return unless the underlying issue is resolved.
Discuss the causes and fixes for P2423 OBDII Code
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