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Home >> GMC >> 1994 >> Forward Control 7.4 N >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - 5.7L >> 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 appropriate TESTS W/O CODES article in this section. See below.

CODE 45 TERMINAL & CIRCUIT WIRING IDENTIFICATION

Application PCM Terminal Wire Color
"C" & "K" Series
5.7L A/T
Oxygen Sensor Signal A10 Purple
Oxygen Sensor Ground A12 Tan
5.7L M/T
Oxygen Sensor Signal D7 Purple
Oxygen Sensor Ground D6 Tan
"G" Series
5.7L A/T
Oxygen Sensor Signal A10 Purple
Oxygen Sensor Ground A12 Tan
"P" Series
5.7L A/T
Oxygen Sensor Signal A10 Purple
Oxygen Sensor Ground A12 Tan
5.7L M/T
Oxygen Sensor Signal D7 Purple
Oxygen Sensor Ground D6 Tan
Fig 1: Code 45 Schematic (5.7L) Rich Exhaust Indication
G91H07378
Fig 2: Code 45 Flow Chart (5.7L) Rich Exhaust Indication
G91A07351