The P033E: Knock Sensor 4 Circuit Intermittent (Bank 2) code indicates that the engine control module (ECM) is detecting intermittent signals from knock sensor 4 in bank 2. Knock sensors detect engine knock (pre-detonation) and send signals to the ECM to adjust engine timing. If the signals from the sensor are inconsistent, it can prevent the ECM from properly adjusting timing, which could lead to engine damage over time.
P033E – Quick Overview
Meaning | P033E: Knock Sensor 4 Circuit Intermittent (Bank 2) |
Is it serious? | Yes, this code can prevent the ECM from accurately detecting engine knock, potentially leading to engine damage if left unresolved. |
Possible causes | – Intermittent sensor failure – Loose connections – Wiring disruptions |
How to diagnose? | – Check for intermittent issues – Inspect and secure connections – Test and repair wiring |
P033E Meaning
The P033E: Knock Sensor 4 Circuit Intermittent (Bank 2) code means that the ECM is receiving inconsistent or intermittent signals from knock sensor 4 in bank 2. This could be due to a sensor malfunction, loose or damaged wiring, or connection issues. Without a consistent signal, the ECM cannot accurately detect and correct engine knock, which can lead to poor engine performance or damage.
Step-by-step diagnostic guide
Follow these steps to diagnose and resolve the P033E code by addressing potential causes one by one.
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to check for any other related codes that may provide further insight into the issue. | OBD-II Scanner |
Inspect Knock Sensor 4 for Issues | Visually inspect knock sensor 4 for signs of wear, corrosion, or damage. Ensure that it is securely mounted and connected. | Flashlight, Safety Gloves |
Check for Intermittent Sensor Failures | Use a multimeter to test knock sensor 4 while gently moving the sensor and wiring to detect any intermittent signal drops. | Multimeter, Manufacturer’s Specifications |
Inspect and Secure Connections | Inspect the wiring and connections leading to knock sensor 4 for signs of looseness, corrosion, or damage. Secure all connections and clean any corroded terminals. | Flashlight, Wiring Repair Kit |
Test and Repair Wiring | Check the wiring for signs of fraying, damage, or loose connections that could cause intermittent signals. Repair or replace any damaged wiring as necessary. | Multimeter, Wiring Repair Kit |
Clear the Code and Test Drive | After repairs, clear the P033E code using an OBD-II scanner. Test drive the vehicle to ensure the problem has been resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
Recheck for Codes | After the test drive, re-scan the vehicle to confirm that the P033E code has not returned. If the code reappears, further diagnosis may be needed. | OBD-II Scanner |
This guide will help you resolve the P033E code, ensuring knock sensor 4 in bank 2 operates correctly, providing consistent signals to protect the engine from knock or detonation.

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)