Wagoneer L6-258 4.2L VIN C 2-bbl (1982)
Distributor Vacuum Control: Description and Operation
Non-Linear Vacuum Regulator (NLVR) Valve
PURPOSE
On engines equipped with a NLVR valve, distributor vacuum advance is controlled primarily by regulated vacuum. Regulation is determined by
engine load.
OPERATION
The NLVR valve has two input ports (one from manifold vacuum and one from carburetor ported vacuum sources) and one outlet port to CTO
valve. Under low-load or no-load operating conditions, the valve provides regulated vacuum. Under these conditions, manifold vacuum is high and
there is little or no ported vacuum. The NLVR valve provides a vacuum level that is somewhere between the two vacuum levels, determined by the
calibration of the valve. As engine load increases and ported vacuum increases above the regulated value, the valve switches to ported vacuum.
