Noobie, Thermostat question

deviantwagon · Post by **deviantwagon** » 15 Feb 2010, 12:21

Hello all, I have read that when the temp gauge never gets the the horizontal point that your thermostat is stuck open...

1. is this true?

2. If true are you guys going with the stock 192 degree one or the optional cooler ones available (180 or even 160)?

2000 Volvo V70 XC SE AWD

Post by **polskamafia mjl** » 15 Feb 2010, 12:25

#1 is true. As to #2, I don't know since I drive an 850. However, if you want the t-stat to open sooner (i.e. you live in a cooler climate) get the lower degree one. If you want it to open later (i.e. you live in a warmer climate) get the higher degree one.

Post by **OEMVolvoParts** » 15 Feb 2010, 16:25

I would also add that the ect sensor tells the gauge (and the ecu) how warm or cold the car is. If your gauge is now showing the car ever gets to operating temp, the ect sensor itself could be to fault. Part number is 9125463 and gasket is 11994.

Post by **mikealder** » 16 Feb 2010, 16:13

Just replaced the thermostat on my V70 for this very reason as the car was over cooling, since swapping out the deffective part the temp gauge is at three o'clock within 3 minutes of driving off with no ECU fail lights on the dash - Well worth a part change as the fuel ecconomy will suffer if its running cold all the time - Mike

Post by **E170_Driver** » 17 Feb 2010, 11:51

My V70 temperature gauge was on the 11 o'clock position when at temperature and I received a OBD-II Trouble Code 0128 Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature). I replaced the thermostat with a 192 C unit and the Code has not returned since then.

Jan

Old Blue 66 · Post by **Old Blue 66** » 17 Feb 2010, 12:15

mikealder wrote:Just replaced the thermostat on my V70 for this very reason as the car was over cooling, since swapping out the deffective part the temp gauge is at three o'clock within 3 minutes of driving off with no ECU fail lights on the dash - Well worth a part change as the fuel ecconomy will suffer if its running cold all the time - Mike

True statement. The t-stat in my car was stuck open in December and my fuel economy went down the tubes. Lost about 3 or 4 mpg.

deviantwagon · Post by **deviantwagon** » 17 Feb 2010, 16:09

Crap it looks like I may have ordered the wrong one ..I have a 180 on the way. Do you think the computer will accept 180 rather than the stock 192 and consider the car warm? Thank you for your replies! I had a couple 240's years ago liked them ...this wagon is a whole different animal...Lovin' it!

proton · Post by **proton** » 18 May 2010, 09:30

I'm trying to understand (english is not my first language) Got an 2005xc70 2 years ago and running an average to 15-16 miles/gal (us) 15-16 L/100. No check engine and no codes. Went to 2 different dealers, one change the MAS. Spark plug and air filter changed often. None found the solution and still having 400km or less on a tank. Not driving like crazy. Last time the dealer let me a 2005 s60 4x4 with the same engine than mine and got 10.5L/100 (us 22.4mi/gal) average for doing the same all around things. What should I check to see if that thermostat thing can be in cause? or any other idea since volvo professionals cant find it.

sorry for my english.

Post by **polskamafia mjl** » 18 May 2010, 16:23

How high does the temp needle go after driving your car around? Normal operating temp is at the halfway point. If your needle is below that most of the time then your thermostat and ECT sensor need to be replaced.

proton · Post by **proton** » 19 May 2010, 07:13

huuumm bit sad..... it is perfectly in the middle, so I need to look elsewhere. Taught I had the finger pointed it. What do you do when 2 dealer say to you no code no clue.... I have to find it myself because they are part changer, not mechanics in my point of view. If you have any hint....