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P0128 Diagnostic Trouble Code Discussion for September 2012

Thermostat System Malfunction


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Trouble Ticket Help Requests for DTC P0128
Help Request Posted
2006 Hummer H3 3.5L Poor Idle Quality, Misfire, MIL Lamp on VIN: 5GTDN13636
P0128: Engine Coolant Temperature Below Thermostat Regulating Temperature. I am having trouble finding a definitive answer to why this vehicle has a misfire on cyl #2 at an idle. The code I have is for a random misfire but watching it on the modis shows cyl #2 missing all the time at an idle. I swapped the ignition coils, swapped the...
September 28, 2012
2006 Hummer H3 3.5L Poor Idle Quality, Misfire, MIL Lamp on VIN: 5GTDN13636
P0128: Engine Coolant Temperature Below Thermostat Regulating Temperature. I am having trouble finding a definitive answer to why this vehicle has a misfire on cyl #2 at an idle. The code I have is for a random misfire but watching it on the modis shows cyl #2 missing all the time at an idle. I swapped the ignition coils, swapped the...
September 29, 2012
2006 Hummer H3 3.5L Poor Idle Quality, Misfire, MIL Lamp on VIN: 5GTDN13636
P0128: Engine Coolant Temperature Below Thermostat Regulating Temperature. I am having trouble finding a definitive answer to why this vehicle has a misfire on cyl #2 at an idle. The code I have is for a random misfire but watching it on the modis shows cyl #2 missing all the time at an idle. I swapped the ignition coils, swapped the...
September 28, 2012
2006 Hummer H3 3.5L Poor Idle Quality, Misfire, MIL Lamp on VIN: 5GTDN13636
P0128: Engine Coolant Temperature Below Thermostat Regulating Temperature. I am having trouble finding a definitive answer to why this vehicle has a misfire on cyl #2 at an idle. The code I have is for a random misfire but watching it on the modis shows cyl #2 missing all the time at an idle. I swapped the ignition coils, swapped the...
September 29, 2012