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Idle Speed Control, ISC II - Revised Features

Model Year 1983

Bulletin No. 83-72

File In Group 64A

Number 9

Date Feb., 83
SUBJECT: Revised Idle Speed Control, ISC II On Certain 1983 Dualjet and Quadrajet Carburetors



A revised Idle Speed Control Assembly was introduced on Dualjet carburetors for the 3.8L V-6 engine (VIN Code 9) in December of 1982. Use has been extended to Quadrajet carburetors used on the 4.1L V-6 engine (VIN Code 4), and Dual jet carburetors used on the 3.0L V-6 engine (VIN Code E), and 3.8L V-6 engine (VIN Code A). The new ISC assembly is identified by the numeral "II" on the motor housing, as shown.

The new feature is a silent throttle contact switch that does not "Click" when actuated. When checking operation of the throttle contact switch on ISC II, follow present Service Manual procedures.