Vacuum Leak Diagnosis

When there is a vacuum leak, the vehicle often has performance issues such as poor acceleration, a rough idle, stalling, and/or poor fuel economy. The Check Engine Light is usually illuminated and the vehicle may misfire.

A Vacuum Leak Diagnosis involves special computer system scan tools, vacuum leak location tools (such as a smoke machine), electronic testing equipment, and specialized technician training.

The purpose of this article is to provide an outline for some of the essential steps involved in performing a Vacuum Leak Diagnosis. This guide can be used—by you and the shop—to track the progress as the mechanics perform the inspections.

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