Is there a way to bleed the cooling system of air? I know the older GM V6's always had a bleeder valve. It was reading 181 95% of the time on a trip today, went down to 172 down a large hill and as high as 217 when we were in stop and go traffic. The whole time the temp gauge never moved, it is always on the 3rd or 4th notch, so either there is air in the system or possibly a faulty sensor? I wonder if the gauge uses a different sensor? Thanks again!

 

Been watching my temps again this afternoon in my 2.2. 180 temp in 70 degree weather with no traffic, when I hit the traffic a little later it went to 205. Pulled in driveway & let it idle-went up to 217-fan kicked in and dropped to 180/1 within a minute yet the fan still stayed on over 5 minutes at 180/1 and didn't turn off till I shut the HHR off. Then restarted and the fan was not on. Odd it didn't shut down by itself after hitting the 180 mark...