Replace knock sensor harness when replacing head gasket on Toyota 4Runner

Submitted by Vehicle Owner · May 29, 2025

Published by RepairPal

Problem overview

The 3.0 V6 engine is usually prone to leaks in the head gasket after as little as 60,000 miles. When the head gasket is replaced, the knock sensor harness should be replaced as well, as it can be damaged by leaky head gaskets, resulting in a serious decrease in fuel efficiency or in long term engine damage.

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Toyota 4Runner vehicles with this problem

6 model years affected

Repairs related to this problem

Head Gasket Replacement

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Replace knock sensor harness when replacing head gasket on Toyota 4Runner

Problem overview

Toyota 4Runner vehicles with this problem

Need a diagnosis? Trust our Toyota experts.

Search for another problem

Ask our experts about your Toyota.

Need a diagnosis? Trust our Toyota experts.

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