Operation CHARM: Car repair manuals for everyone.

Intake Restriction





PURPOSE
This is visual inspection to determine if intake restriction is contributing to a low power condition. If the engine does have high inlet restriction, a considerable amount of black or blue smoke may be produced.

RECOMMENDED PROCEDURE
Inspect the air cleaner inlet and ducting to assure that it is not blocked or collapsed. Inspect air cleaner housing and filter for proper installation.

Magnehelic Gauge / Air Restriction Gauge:






If necessary, install a Magnehelic(R) gauge on the port on the air cleaner and measure restriction at high idle.

POSSIBLE CAUSES
Snow, plastic bags or other foreign material may block the air cleaner inlet. Misrouted air cleaner ducting may collapse when the hood is shut. On engines recently repaired, rags or cap plugs may have been inadvertently left in an intake pipe.

TOOLS REQUIRED
Magnehelic(R) gauge