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P0128 Diagnostic Trouble Code Discussion for December 2013

Thermostat System Malfunction


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Trouble Ticket Help Requests for DTC P0128
Help Request Posted
2008 Land Rover Range Rover Sport Supercharged 4.2L Hard starting VIN: SALSH23478
P0128: Coolant Thermostat. This Land Rover has a very difficult time starting when cold. We have been between 5*F and 25*F the last couple of weeks, and this is when the issue occurs. It will crank over fine, but coughs and sputters and tries to start, but won't. It has the push-button ...
December 11, 2013
2006 Cadillac CTS 3.6L Misfire VIN: 1G6DP57756
P0128: ECT Excessive Time To Enter Closed Loop. I am not familiar with this engine. Live data on scan tool shows miss's in cylinders #1 & #2 but primarily in #1. History shows miss in cylinders #1, #2, #3 & #4. Miss seems to be constant both at idle and while driving. Oil is about a quart high &...
December 16, 2013
2005 Hyundai Santa Fe 2.7L MIL Lamp on
P0128: Coolant Thermostat. trk brought to shop w/mil lite on and a concern for a 1800 rpm idle @ cold start up. coolant temp sensor code present. check @ coolant sensor plug for 5v reference signal, ok. pulled t/stat off to check for being stuck open,ok. did back pressure test on both c...
December 31, 2013
2005 Hyundai Santa Fe 2.7L MIL Lamp on
P0128: Coolant Thermostat. trk brought to shop w/mil lite on and a concern for a 1800 rpm idle @ cold start up. coolant temp sensor code present. check @ coolant sensor plug for 5v reference signal, ok. pulled t/stat off to check for being stuck open,ok. did back pressure test on both c...
December 31, 2013
2008 Land Rover Range Rover Sport Supercharged 4.2L Hard starting VIN: SALSH23478
P0128: Coolant Thermostat. This Land Rover has a very difficult time starting when cold. We have been between 5*F and 25*F the last couple of weeks, and this is when the issue occurs. It will crank over fine, but coughs and sputters and tries to start, but won't. It has the push-button ...
December 11, 2013
2006 Cadillac CTS 3.6L Misfire VIN: 1G6DP57756
P0128: Engine Coolant Temperature Below Thermostat Regulating Temperature. I am not familiar with this engine. Live data on scan tool shows miss's in cylinders #1 & #2 but primarily in #1. History shows miss in cylinders #1, #2, #3 & #4. Miss seems to be constant both at idle and while driving. Oil is about a quart high &...
December 16, 2013
2005 Hyundai Santa Fe 2.7L MIL Lamp on
P0128: Coolant Thermostat. trk brought to shop w/mil lite on and a concern for a 1800 rpm idle @ cold start up. coolant temp sensor code present. check @ coolant sensor plug for 5v reference signal, ok. pulled t/stat off to check for being stuck open,ok. did back pressure test on both c...
December 31, 2013