A CONDITION OF TROUBLE CODE 42 BEING SET IN A 1983 CUTLASS SUPREME EQUIPPED WITH A 3.8L V-6 ENGINE (VIN CODE A AND 1983 CIERA EQUIPPED WITH 3.0L V-6 ENGINE-VIN CODE E) COULD BE CAUSED BY THE EST HARNESS BEING ROUTED TOO CLOSE TO SPARK PLUG WIRE. THIS MAY CAUSE EST SIGNALS SENT FROM THE ECM TO BE INTERRUPTED BY THE ELECTRO MAGNETIC FIELD CREATED BY SPARK PLUG FIRING. TO CORRECT THIS CONDITION ROUTE NO. 2, 4 AND 6 SPARK PLUG WIRES TO THE INSIDE OF THE ENGINE LIFT HOOK AND THE EST HARNESS UNDER AND AROUND THE DISTRIBUTOR. (SEE FIGURE). ALSO, MAKE SURE THE TPS AND ISC HARNESSES ARE ROUTED BELOW THE CANISTER PURGE HOSE. (SEE ILLUSTRATION)
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