The Walker Products Ignition Knock (Detonation) Sensor (part number 242-1038) is a direct-fit replacement for 1999-2002 Subaru vehicles with 2.5L and 2.2L engines. Walker Products Knock Sensors are OE Replacement components that detect engine detonation to help the ECU adjust timing and prevent internal engine damage.
Features:
- OE Replacement Sensitivity:Â Calibrated to match factory frequency response and output for seamless ECU integration and spark control.
- Exact OE Fit: Installs directly into original mounting locations using factory connectors and threads—no modifications required.
- Built for Harsh Environments:Â Engineered to resist heat, vibration, and oil exposure for long-lasting signal reliability.
- Detects Engine Knock:Â Monitors vibration frequencies to detect detonation and prevent pre-ignition engine damage.
- Restores Ignition Timing Accuracy:Â Supports optimal fuel efficiency, performance, and emissions by correcting spark advance during knock conditions.
Specifications:
| Number of Terminals | 1 |
| Connector Type | Blade |
| Connector Shape | Oblong |
| Connector Gender | Male |
| Terminal Gender | Female |
Fits: 1999-2002 Subaru models including Forester, Impreza, Legacy, and Outback — 2.5L and 2.2L engines.
Confirm the year, make, model, and engine against your vehicle before ordering. Full application data is shown in the fitment lookup on this page.
Interchanges With: Dorman 917031, NTK ID0198, ERA 550595, Standard Import 70037, KEM 144-745, Lucas Electrical SEB2107, Meat & Doria 87591, Wells SU4990 and 18 more
WARNING: This product can expose you to chemicals, including lead, which is known to the State of California to cause cancer or birth defects or other reproductive harm.
