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Home >> Buick >> 1994 >> Roadmaster Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - 5.7L >> ECM/Pcm Code Charts >> Code 45, Left Heated Oxygen Sensor Circuit Rich Indication >> EGR Problem
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EGR Problem

EGR valve sticking open at idle is usually accompanied by a rough idle and/or stalling. Also check for shorted or leaking injector and fuel-contaminated oil. If Code 45 is intermittent, see INTERMITTENTS in TESTS W/O CODES article in this section.

CODE 45 PCM TERMINAL & CIRCUIT WIRING IDENTIFICATION

Application PCM Terminal Wire Color
Left O2 Signal C20 Purple/White
Left O2 Ground C19 Tan/White
Fig 1: Code 45 Schematic (5.7L) Rich Exhaust Indication
G91H07378
Fig 2: Code 45 Flow Chart (5.7L) Rich Exhaust Indication
G91A07351