Page text (OCR transcript)
EMISSION CONTROL SYSTEMS — Dash Pot (DP) System EC-7
DASH POT (DP) SYSTEM
[Diagram showing VTV, Air Filter, and Dash Pot components]
Normal Driving Deceleration
DP Diaphragm DP Diaphragm
VTV VTV
EC2134 EC2134
To reduce HC and CO emissions, when decelerating the dash pot opens the throttle valve slightly more than at idle.
This causes the air-fuel mixture to burn completely.
Condition Diaphragm VTV Throttle Valve
Idling Pushed in by return force of CLOSED Idle speed position
throttle valve
Normal driving Pushed out by diaphragm spring OPEN High speed position
Deceleration Pushed in by return force of CLOSED Slightly opens and then slowly closes
throttle valve to idle position