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Home >> GMC >> 1996 >> Forward Control 4.3 W >> Repair and Diagnosis >> External Pages >> Different car >> Section 126 (Engine Controls - Tests W/Codes - 4.3L) >> Trouble Code Charts >> Code 45, Rich Exhaust Indication - All Models >> EGR Problem

EGR Problem

WARNING: This page does not describe the selected car, but rather 19 other vehicles, including the 1996 Chevrolet Chevy Van, 1995 GMC Vandura Special, 1995 GMC Vandura, 1995 GMC Sonoma, and 1995 GMC Safari. However, it is still accessible from the selected car via links, so may be relevant.

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 - GASOLINE article.

CODE 45 TERMINAL & CIRCUIT WIRING IDENTIFICATION

Application ECM/PCM Terminal Wire Color
"C" & "K" Series
4.3L
Oxygen Sensor Signal A10 Purple
Oxygen Sensor Ground A12 Tan
"G" Series
4.3L A/T
Oxygen Sensor Signal A10 Purple
Oxygen Sensor Ground A12 Tan
"L" & "M" Series
4.3L
Oxygen Sensor Signal A10 Purple
Oxygen Sensor Ground A12 Tan
"P" Series
4.3L
Oxygen Sensor Signal A10 Purple
Oxygen Sensor Ground A12 Tan
"S" & "T" Series
4.3L (VIN W) Pickup & A/T Utility
Oxygen Sensor Signal A10 Purple
Oxygen Sensor Ground A12 Tan
4.3L (VIN Z) A/T Pickup
Oxygen Sensor Signal A10 Purple
Oxygen Sensor Ground A12 Tan
Fig 1: Code 45 Schematic (4.3L) Rich Exhaust Indication
G91H07378
Fig 2: Code 45 Flow Chart (4.3L) Rich Exhaust Indication
G91A07351