Hello,
On my 1995 Volvo 850 T5 Sedan, it seems that no matter how far I drive, the temperature gauge stays almost at the bottom (maybe 5 o clock). When I park the car after driving and let it idle just for a few minutes, it goes almost half way up. I have only had the car for a couple of weeks, but since then, all the driving I have done has been below freezing. Around -10*F below zero to 20*F above zero. Is there something wrong that makes it always seem to be running cold?

-Thanks

 

Hi Keith,

I assume the thermostat is probably partially stuck open (a fully stuck-open thermostat also causes overheating in hot climate, as the coolant passes through the radiator without enough time to give off heat), and when you drive the car the ram air cools coolant, which is probably keeping the temp gauge at the bottom.

I would have it serviced ASAP, as it affects fuel consumption & other things. If you have some hand tools (Torx bits are a must to work on Volvos & many other makes) and common sense for safety, the replacement is very easy and is well within DIYer's capability. There are 2 OEMS I know of; Vernet (French) and Wahler (German).


JPN

 

I agree on thermostat.

 

Thanks a lot for the advice.

Do you think running the car like that (as it probable has for a while) and using it like that until I get it fixed in a week or so will do any harm? It is not overheating so I assume there is no huge issue. It is just cooler than it should be.

-Thanks

 

No harm, but the car will run completely different from as if it were operating 100%.

Your heat won't work right and I believe the car runs richer (or leaner, I forget which and I don't want to think about which one right now lol).

 

Agreed - thermostat. Check out this resource for some more information (scroll down to "water cooling" near the bottom): http://www.carbibles.com/fuel_engine_bible.html

Quote:
Water cooling is the most common method of cooling and engine down, but it's also the most complicated. For example you don't want the coolant flowing through the radiator as soon as you start the engine. If it did, the engine would take a long time to come up to operating temperature which causes issues with the emissions systems, the drivability of the engine and the comfort of the passengers. In truly cold weather, most water cooling systems are so efficient that if the coolant flowed through the radiator at startup, the engine would literally never get warm. So this is where the thermostat comes in to play.

 

Replacing Thermostat and Coolant Temp Sensor...

https://volvoforums.com/m_16392/tm.htm

 

Ditto on the thermostat. Are you even getting any heat out of it? I would check the radiator hoses while you are at it as well as replace the T-stat.

Glenn