Possible causes

– Faulty Oxygen sensor
– Ignition problem
– Fuel injection problem
– Engine mechanical condition

Tech notes

There is a factory service bulletin for the following Pontiac models:

2000-2001 Pontiac Transport
2000-2002 Pontiac Firebird
2000-2008 Pontiac Bonneville
2000-2008 Pontiac Grand Am
2000-2008 Pontiac Grand Prix
2000-2008 Pontiac Sunfire
2001-2008 Pontiac Aztek
2002-2008 Pontiac Montana
2000-2008 Pontiac Factory Service Bulletin OBDII Code P1175

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)

P1175 PONTIAC Description

The Engine Control Module (ECM) performs a fuel trim cylinder balance utilizing the HO2S, when the calculated accumulated voltage exceeds a predetermined level this code is set