P2344 OBD-II Trouble Code: Cylinder #9 Above Knock Threshold

Our certified mechanics come to you · Get a fair and transparent estimate upfront

Red-stars EXCELLENT RATING ON

Cost of diagnosing the P2344 code

P2344 is a diagnostic trouble code (DTC) for "Cylinder #9 Above Knock Threshold". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic. Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $20.00 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.

Cars Estimate Credit towards follow-up repair Earliest Availability
Ford$20.00
Toyota$20.00
BMW$20.00
SCHEDULE P2344 DIAGNOSTIC Get a fair and transparent estimate upfront

P2344 code definition

This is the generic trouble code for Cylinder #9 Above Knock Threshold.

What the P2344 code means

When a vehicle sets this code it means that the PCM (powertrain control module) has received a voltage input reading from the cylinder 9 knock sensor circuit that is not within the expected parameters. The purpose of the knock sensor is to alert the PCM to any abnormal noises related to cylinder detonation. The sensor serves as a type of microphone, carefully monitoring the ping that a cylinder makes when it fires. Knock sensor circuits are typically made up of a five-volt signal wire.

What causes the P2344 code?

A number of conditions may cause a vehicle to store this DTC:

  • A faulty knock sensor
  • Damaged or corroded wires or connectors, or loose connections
  • Abnormal fuel to air ratio causing an anomaly in cylinder detonation
  • Other cylinder firing malfunctions

When a vehicle stores this code, it is often indicative of a more serious underlying problem. While the knock sensor itself may be faulty, the abnormal voltage signal could also be the result of an engine malfunction.

What are the symptoms of the P2344 code?

The Check Engine Light will illuminate, either staying on for long periods of time, staying on all the time, or coming on and going off intermittently. You may also notice sluggish acceleration, reduced power while driving, and spark knock. Spark knock is the result of fuel detonation rather than the expected smooth burn as a cylinder fires. It’s also known as pinging or engine knock.

How does a mechanic diagnose the P2344 code?

Diagnosing this DTC may require:

Common mistakes when diagnosing the P2344 code

One of the most common errors is to automatically replace the knock sensor, assuming it must be faulty, without also investigating other underlying causes of the problem. It could very well be that the sensor is performing its job of alerting the PCM of a serious issue.

How serious is the P2344 code?

This DTC should be addressed as soon as possible due to the potential for an engine malfunction which could compromise safety as well as the engine’s integrity if allowed to go unchecked.

What repairs can fix the P2344 code?

Repairs for this code may include:

Additional comments for consideration regarding the P2344 code

Experts highly recommend always addressing any DTCs that have stored prior to the current code. In the case of the cylinder #9 above knock threshold error, it is particularly crucial to diagnose and repair any other problems which are present at the same time. This is due to the fact that P2344 often sets when something else is causing the engine to produce detonation and make more noise than it should. When this happens, the engine adjusts its timing in order to protect itself – this can affect other components and change the way the engine functions.

Knock sensors may be situated in a way that makes them difficult to access for testing. If this is the case with your vehicle, the sensor may need to be diagnosed using a process of elimination. Once all other possible causes have been ruled out, it may be prudent to assume the sensor is faulty.

Need help with a P2344 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

trouble codes
P2344
Check Engine Light

No more waiting rooms! Our mechanics will come to you to diagnose and fix the P2344 code.

SCHEDULE P2344 DIAGNOSTIC
Get a $20 credit for the follow-up repair

Recent Check Engine Light is on Inspection reviews

Excellent Rating


YourMechanic Check Engine Light is on Inspection Service

Average Rating

4.8/5

Number of Reviews

5,626

Rating Summary
5,199
206
50
34
137
5,199
206
50
34
137

Robert

11 years of experience
104 reviews
Robert
11 years of experience
Nissan Quest - Check Engine Light is on - Alexandria, Virginia
Punctual. Knowledgeable. Professional. Empathic, went the extra mile to explain in lay words the mechanical jargon. Excellent manners and customer service oriented. Client’s best interest and safety was always his top priority. From now on your company has in me a client for life. Thanks Robert!!!! 

Chris

21 years of experience
1861 reviews
Chris
21 years of experience
Mercedes-Benz E320 - Check Engine Light is on - Ladera Ranch, California
Chris was friendly, professional and knowledgeable. He got to the point of my concerns, explained what he was finding on his system and gave me his recommendations. I fully appreciate him taking the time to explain everything and a bit of history on my vehicle. Thanks again Chris.

Michael

15 years of experience
574 reviews
Michael
15 years of experience
Hyundai Accent - Check Engine Light is on - Marietta, Georgia
I had a great experience with Michael. He's extremely professional, friendly, and understands his craft. Highly recommended.

Chris

15 years of experience
274 reviews
Chris
15 years of experience
Dodge Durango - Check Engine Light is on - San Diego, California
Showed up early, was a friendly dude, kept me informed via text, did clean work and finished early. Would hire again.


More related articles

P2077 OBD-II Trouble Code: Intake Manifold Tuning (IMT) Valve Position Sensor/Switch Circuit Low
P2077 P2077 code definition Intake Manifold Tuning (IMT) Valve Position Sensor/Switch Circuit Low What the P2077 code means P2077 is an OBD-II generic code for the Engine Control Module (ECM), detecting the intake manifold tuning valve position sensor circuit Pulse...
P0878 OBD-II Trouble Code: Transmission Fluid Pressure Sensor/Switch D Circuit High
P0878 means the PCM has detected an abnormal pressure within the transmission fluid sensor/switch often due too low fluid levels or malfunction.
P0341 OBD-II Trouble Code: Camshaft Position Sensor Circuit Range/Performance
P0341 code definition Camshaft Position Sensor Circuit Range/Performance What the P0341 code means P0341 is an OBD-II generic code that says the...

Related questions

Check Engine light on with a misfire in cylinder 1

Hello. Although you have just replaced the spark plug and coil pack, there could be several things going on here. It is possible that the wiring to the coil pack is broken, there could be a broken wire somewhere, or...

CEL slow higher rpms

Hello there, thank you for asking about your 2013 BMW 135i. The very first thing I would do is have the vehicle scanned for trouble codes, as sputtering and a Check Engine Light can be caused by a wide variety...

Check engine light, EGR.

Hi. The next step to take with this issue is to clean out the passages that EGR valve sits on top of. These passages get clogged up with carbon and causes the EGR valve to look bad to the computer...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (855) 347-2779 · hi@yourmechanic.com