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Home >> GMC >> 1992 >> Forward Control 4.3 Z, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - V6 >> Trouble Code Charts >> Code 45, Rich Exhaust 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. If Code 45 is intermittent, see INTERMITTENTS in TESTS W/O CODES article.

CODE 45 ECM TERMINAL & CIRCUIT WIRING ID (ALL W/4L80-E A/T)

Application ECM Terminal Wire Color
O2 Sensor Signal C14 Purple
O2 Sensor Ground C13 Tan
CODE 45 ECM TERMINAL & CIRCUIT WIRING ID (ALL OTHERS)

Application ECM Terminal Wire Color
O2 Sensor Signal D7 Purple
O2 Sensor Ground D6 Tan
Fig 1: Code 45 Schematic (Except 4.3L Turbo) Rich Exhaust Indication
G91H07378
Fig 2: Code 45 Flow Chart (Except 4.3L Turbo) Rich Exhaust Indication
G91A07351


EGR valve sticking open at idle is usually accompanied by a rough idle and/or stalling. If Code 45 is intermittent, see INTERMITTENTS in TESTS W/O CODES article.

Fig 1: Code 45 Schematic (4.3L Turbo) Rich Exhaust Indication
G91E13734
Fig 2: Code 45 Flow Chart (4.3L Turbo) Rich Exhaust Indication
G91A13714