Engine Code 52 (Knock Sensor) - Rear Knock Sensor Wiring Repair

Engine throws diagnostic Code 52 (knock sensor fault), causing the ECU to retard timing significantly, resulting in severe power loss comparable to a much weaker car.

The rear knock sensor's single wire lead becomes frayed or develops a bad connection over time. The knock sensors are located on the driver's side of the engine block under the intake manifold, and the rear sensor (Code 52) is particularly prone to wiring degradation due to its location near the firewall and steering column. In approximately 90% of cases, the issue is the wiring rather than the sensor itself.

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