Dashpot System Check
- Connect tachometer to engine. Start engine and allow to reach normal operating temperature (cooling fan on). Disconnect vacuum hose from throttle control valve.
- Connect hand vacuum pump to throttle control valve and apply 8 in. (200 mm) Hg vacuum. Check that engine speed rises (within 1 minute) to 1500-2500 RPM on Accord and Prelude models or 1200-2200 RPM on Civic models.
- If speed was too low, widen the adjusting slot in the throttle control valve lever with a screwdriver. If speed was too high, narrow the slot with pliers. If speed cannot be adjusted, or diaphragm will not hold vacuum, replace the throttle control valve and retest. See Fig 2.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Courtesy of AMERICAN HONDA MOTOR CO., INC.