Nissan Z - ZX 1970-1988 Repair Guide

Boost Controlled Deceleration Valve


This unit is used on all 1975 and later models (except turbo engines), to perform the same function as the throttle opener used on earlier models, to reduce emissions of HC during deceleration. The valve is a part of the throttle chamber and is located at the bottom. If the throttle hangs open for long periods during deceleration, it is a sign that the valve requires adjustment. This should be referred to your local Nissan dealer.