Check Valve Operation Check: Notes

WARNING: This page is about a different variant/trim than selected.

CAUTION: The check valve should not be removed from the vacuum hose.

Remove the vacuum hose. (Refer to MASTER CYLINDER ASSEMBLY AND BRAKE BOOSTER .)
CAUTION: If the check valve is defective, replace it as an assembly together with the vacuum hose.

Check the operation of the check valve by using a vacuum pump.

VACUUM PUMP SPECIFICATION

VACUUM PUMP CONNECTION	CRITERIA
Connection at the brake booster side (A)	A negative pressure (vacuum) is created and held.
Connection at the intake manifold side (B)	A negative pressure (vacuum) is not created.

Fig 1: Measuring Check Valve Operation

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.