Possible causes
– Faulty Oxygen sensor
– Ignition problem
– Fuel injection problem
– Engine mechanical condition
– Ignition problem
– Fuel injection problem
– Engine mechanical condition
Tech notes
There is a factory service bulletin for the following HUMMER models:
2003-2008 HUMMER H2
2003-2008 HUMMER Factory Service Bulletin OBDII Code P1174
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
P1174 HUMMER 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
HUMMER Technical Service Bulletins for P1174 code
2006 HUMMER H3 FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:INJECTORS
2007 HUMMER H3 FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:INJECTORS
2003 HUMMER H2 FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:INJECTORS
2004 HUMMER H2 FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:INJECTORS
2005 HUMMER H2 FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:INJECTORS
2006 HUMMER H2 FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:INJECTORS
2007 HUMMER H2 FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:INJECTORS