Hi,

I am new to this forum and having done a search I cannot find an answer to my question. I have a 1.6Tdci which I suspect is running colder than it should do. The temperature takes a while to reach near to 90° (88° perhaps assuming each division is 15°). The temp will then drop down to nearer 75° (2nd division) and then hover between 75 and 80ish). The temperature never reaches 90° again. The question is therefore how much the temp needle moves once up to temperature and what temperature does it maintain under normal circumstances. It has been cold outside recently, but I would think the block should heat up relatively quickly if thermostat is not open given that the car is in a garage overnight. I have check the coolant level and it is near to maximum, so I am suspecting a faulty thermostat but am not sure.

Any help appreciated. I will check the top hose when I get a chance to see if it an open thermostat. Running the car in the garage for 10 minutes does not cause the needle to budge from 60° (cold position)

Thanks

Andrew

Hi,

I am new to this forum and having done a search I cannot find an answer to my question. I have a 1.6Tdci which I suspect is running colder than it should do. The temperature takes a while to reach near to 90° (88° perhaps assuming each division is 15°). The temp will then drop down to nearer 75° (2nd division) and then hover between 75 and 80ish). The temperature never reaches 90° again. The question is therefore how much the temp needle moves once up to temperature and what temperature does it maintain under normal circumstances. It has been cold outside recently, but I would think the block should heat up relatively quickly if thermostat is not open given that the car is in a garage overnight. I have check the coolant level and it is near to maximum, so I am suspecting a faulty thermostat but am not sure.

Any help appreciated. I will check the top hose when I get a chance to see if it an open thermostat. Running the car in the garage for 10 minutes does not cause the needle to budge from 60° (cold position)

Thanks

Andrew

diesels take longer to heat up sitting idling it wont get up to temp youll need to take it for a run then check the top and bottom hose needle should sit in the middle thermostats usually dont fully open till 90 i doubt you have much to worry about when the cars cold the coolant should be midway halfway between min and max and then it expands up to the max line sometimes slightly above

diesels take longer to heat up sitting idling it wont get up to temp youll need to take it for a run then check the top and bottom hose needle should sit in the middle thermostats usually dont fully open till 90 i doubt you have much to worry about when the cars cold the coolant should be midway halfway between min and max and then it expands up to the max line sometimes slightly above

Thanks for the reply. My other observation is that once upto just below 90C the temp will drop, and then the temperature will vary between 75 and 80C or so. I had presumed that the thermostat would maintain the water temperature in a closer range and nearer to 90C. There seems to be too much variation to me for a correctly functioning thermostat. I will investigate and post my findings.

diesels take longer to heat up sitting idling it wont get up to temp youll need to take it for a run then check the top and bottom hose needle should sit in the middle thermostats usually dont fully open till 90 i doubt you have much to worry about when the cars cold the coolant should be midway halfway between min and max and then it expands up to the max line sometimes slightly above

could be the coolant sensor and not the actual thermostat

could be the coolant sensor and not the actual thermostat

I just checked the top hose in the garage having started the car from cold. It remains cold until the car eventually got up to temperature (about 87C as a guess from the gauge). The temperature gauge then stayed steady even with the engine revved. The fan came on etc. This leads me to think that the thermostat is opening properly but perhaps not closing again at the correct temperature, and hence when I am driving the temperature drops suddenly to near 75C once the thermostat opens.