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MK4 ALH TDI - Running Cold

2.3K views 1 reply 2 participants last post by  Kidkinetic  
#1 ·
My 2002 Jetta Wagon TDI (ALH) runs at normal temperature on warm summer days, 90 degrees or above. The rest of the year, it runs cold. On days with 60 degrees or less the temperature gage pretty much doesn't move. Could the thermostat be stuck open? Or could it be a faulty temperature sensor? Let me know if you have any suggestions. Thanks.