Engine Temperature
 

We have Chrysler Grand Voyager 2.8 crd, and by the user manual working engine temperature should be 80C. In our case it is 72-75C. If you switch off the car climate control, then temperature goes up to 80. Do we need to change a thermostat?

The origional thermostat is a huge job, but go to youtube.. https://www.youtube.com/watch?v=MpfQLsWLiic

This worked for me.

Do you have an actual problem ?.

Your engine is @ 80, you by your own figures are taking 5 to 8 degrees of heat from your engine and sending it into your cabin area. When you switch off your cabin heater the engine returns to 80, therefore you thermostat is working fine.

A stat is merely a plug of hard wax that melts in this case @ 80 and allows a heavy duty spring to open a valve allowing water to be pumped around the whole system. Stats are all manufactured so that if they ever fail they fail in the open position, this means (1) water will always flow around the whole engine and (2) the engine and heater will take forever in the cold weather to get warm.

cabin heater
 

How do you turn off the cabin heater? Mine seems to run all the time.
Maybe the answer to my fuel consumption.

MariaGrinchuk, how are you measuring the temperature of coolant (I'm assuming this is coolant temperature and not engine temperature), are you using ODB-II output I'd guess? This is a reasonable way of checking temperature, what does it show on your needle gauge on the car, it should get up to half way after a short-ish journey (10-15 minutes) and stay there afterwards.

Your cabin heater will be on if it's cold and you have the heaters/blowers on.
chuckberry there isn't a manual/easy way of turning the cabin heater off, just turn your in-car temperature right down and after a few minutes it should turn off. It's setup to regulate itself so you shouldn't need to force it to turn off. If you've got a working thermostat and your temperature needle gets to halfway it should shut off on it's own. If you never get to half way then you probably need to replace (or retro-fit as you mention on my video) thermostat. If you've done that though and still low temperature then that would suggest your radiator may be blocked up and needs replacing or at least a coolant change to see what gunk you've got in there.

(And yes, it does affect fuel consumption as diesels like to run warm, at cold they are less efficient)

I just use the PWR button to turn mine off.

thanks Andy. Alan C my car is 2006 I don't see a pwr control. is there one.

Yes LHS marked PWR, also HI / LOW, left UD and right UD etc.

Thanx mate I will check that tomorrow.

This is the location of the PWR switch on both the 2004 and 2007 GV's that I've owned.