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Home >> GMC >> 1990 >> Forward Control 6.2 J, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - Diesel >> Diagnostic Charts >> Code 23, Throttle Position Sensor MISADJUSTED >> Diagnostic Aids
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Diagnostic Aids

Disregard Code 23 if SERVICE ENGINE SOON light goes out when throttle is returned to idle.

Fig 1: Code 23: Circuit Diagram & Flow Chart TPS Misadjusted
G90A13979
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