Tapping Noise From Dash Area - keywords booster brake hose IP IPC line PIINSI purge solenoid tap tick vacuum valve

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Tapping Noise from dash area. This noise is more pronounced on left side of the dash. The tapping noise does not change in tempo, when the engine speed is increased. The evaporator purge solenoid valve plastic line and the brake booster vacuum hose may come in contact with each other. The pulsating of the purge solenoid is transmitted thru the vacuum brake booster hose and is amplified by the vacuum booster into the cab.

Check the routing of the brake booster vacuum hose and the purge solenoid valve plastic line. The brake booster hose should be routed under the purge solenoid plastic line. There should be gap between the brake booster hose and the purge plastic line. See Picture Below

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.