Dashpot System

WARNING: This page is about a different car, the 1992 Acura NSX and 1991 Acura NSX. However, it is still accessible from the selected car via links, so may be relevant.

The dashpot is employed to slow the closing of the throttle valve during gear shifting or deceleration. See Fig 1 .

Check the vacuum line for leaks, blockage or a disconnected hose. See Fig 2 .
Disconnect the vacuum hose from the dashpot diaphragm, and connect a vacuum pump to the hose.
Apply vacuum and check the speed the vacuum goes out. Vacuum should go out slowly. If the vacuum holds or goes out quickly, replace the dashpot check valve and retest.
Connect a vacuum pump to the dashpot diaphragm. See Fig 3 .
Apply vacuum and check that the rod pulls in and vacuum holds. If the vacuum does not hold or the rod does not move, replace the dashpot diaphragm and retest.

Fig 1: Identifying Dashpot System Circuit

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Fig 2: Checking Dashpot Diaphragm Check Valve

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Fig 3: Checking Dashpot Diaphragm For Vacuum Leak

Courtesy of AMERICAN HONDA MOTOR CO., INC.