The P2336: Cylinder 1 Above Knock Threshold code indicates that the knock sensor has detected engine knock or detonation levels in Cylinder 1 that exceed acceptable limits. This knock could be due to several factors, such as a faulty knock sensor, improper ignition timing, or issues with the fuel mixture. Engine knock, if not addressed, can lead to significant damage to the engine components.
P2336 – Quick Overview
Code | Information |
---|---|
Meaning | P2336: Cylinder 1 Above Knock Threshold |
Is it serious? | Yes, excessive engine knock can cause severe damage to engine components, including pistons, valves, and bearings. Immediate diagnosis and correction are required to prevent costly repairs. |
Possible causes | – Excessive engine knock or detonation – Faulty knock sensor – Ignition timing or fuel mixture issues |
How to diagnose? | – Inspect and test the knock sensor – Check ignition timing and fuel mixture – Diagnose potential causes of engine knock |
P2336 Meaning
The P2336: Cylinder 1 Above Knock Threshold code is triggered when the knock sensor detects knock (pinging) levels in Cylinder 1 that are above the acceptable range. Knock occurs when fuel in the cylinder detonates prematurely, which can be due to improper fuel-air mixture, incorrect ignition timing, or a failing knock sensor. If not corrected, it can lead to engine damage, such as piston failure or other severe mechanical issues.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to determine if there are any additional fault codes related to the engine knock, fuel system, or ignition timing. Related codes may provide more context about other underlying issues. | OBD-II Scanner |
Inspect Knock Sensor for Cylinder 1 | Visually inspect the knock sensor associated with Cylinder 1 for signs of damage, such as cracks, loose mounting, or wiring problems. A faulty knock sensor can provide incorrect readings, causing the code to trigger. | Flashlight, Safety Gloves |
Test the Knock Sensor | Use a multimeter to check the resistance of the knock sensor. Compare the readings to the manufacturer’s specifications. Replace the sensor if the readings are out of range or if it fails to respond properly when tested. | Multimeter |
Check Wiring and Connections | Inspect the wiring and connections to the knock sensor for any signs of damage, fraying, or loose connections. Damaged wiring can interfere with proper sensor readings. | Flashlight, Multimeter |
Inspect Ignition Timing | Use a timing light to check the ignition timing. Ensure that the timing is set according to the manufacturer’s specifications. Incorrect timing can lead to detonation, which triggers the knock sensor. | Timing Light |
Inspect Fuel Quality and Mixture | Check the fuel quality and inspect for any potential contamination. Use a fuel pressure gauge to measure the fuel pressure and ensure that the fuel system is delivering fuel at the correct rate. Additionally, verify that the fuel-air mixture is within the ideal range to prevent detonation. | Fuel Pressure Gauge |
Check for Carbon Deposits | Inspect the cylinder and intake components for excessive carbon deposits. Deposits can increase compression and lead to pre-ignition. Carbon cleaning may be required if buildup is excessive. | Inspection Camera |
Verify ECM Knock Retard Function | Use a scan tool to verify that the ECM is adjusting ignition timing in response to knock sensor input. If the ECM is not properly adjusting, there may be an issue with ECM programming or function. | Diagnostic Scan Tool |
Replace Faulty Components if Necessary | If the knock sensor, wiring, or other components are determined to be faulty, replace them with OEM parts to ensure proper function and compatibility. | Replacement Parts, Hand Tools |
Clear the Code and Test Drive | After completing repairs, clear the P2336 code using an OBD-II scanner. Start and test drive the vehicle under varying loads to determine if the engine knock returns or if the sensor records any more excessive knocks. | OBD-II Scanner, Vehicle Owner’s Manual |
Recheck for Codes | After the test drive, re-scan the vehicle to verify that the P2336 code has not returned. If the code persists, additional diagnostics focusing on the ECM or more detailed analysis of cylinder function may be necessary. | OBD-II Scanner |

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Hi, I am Juraj “Yuri” Lukacko. I got frustrated by unhelpful and scammy mechanics, so I decided to learn everything about car diagnostics myself. I test dozens of new car diagnostic tools every month along with learning new strategies to fix and customize cars. About Juraj Lukacko (Yuri)