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P0128 Diagnostic Trouble Code Discussion for December 2009

Thermostat System Malfunction


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Trouble Ticket Help Requests for DTC P0128
Help Request Posted
2004 Pontiac Grand Prix GTP 3.8L hard start VIN: 2G2W552234
P0128: Engine Coolant Temperature Below Thermostat Regulating Temperature. This customer is complaining of hard start. It takes multiple attempts for the engine to start. We experienced three key cycles. The puzzling thing is when we first hooked up the fuel gouge the pressure was zero. Turn the key on but not start the pressure is 1...
December 04, 2009
2003 Chevrolet Trailblazer LT 4.2L MIL Lamp on VIN: 1GNDT13573
P0128: Engine Coolant Temperature Below Thermostat Regulating Temperature. This vehicle has had coolant temp codes in each of the last three years. About every 20k the light comes on. We have flushed the cooling system during that period and replaced the thermostat on two occassions already. There are hits for a problem in the coolan...
December 30, 2009
2004 Pontiac Grand Prix GTP 3.8L hard start VIN: 2G2W552234
P0128: Engine Coolant Temperature Below Thermostat Regulating Temperature. This customer is complaining of hard start. It takes multiple attempts for the engine to start. We experienced three key cycles. The puzzling thing is when we first hooked up the fuel gouge the pressure was zero. Turn the key on but not start the pressure is 1...
December 04, 2009
2003 Chevrolet Trailblazer LT 4.2L MIL Lamp on VIN: 1GNDT13573
P0128: Engine Coolant Temperature Below Thermostat Regulating Temperature. This vehicle has had coolant temp codes in each of the last three years. About every 20k the light comes on. We have flushed the cooling system during that period and replaced the thermostat on two occassions already. There are hits for a problem in the coolan...
December 30, 2009