Hi all,

I've got a 94 850 T wagon (138K) that I bought about 3 months ago and it started "overcooling" on my a few days ago. I just assumed it was a stuck t-stat (as did all my car buddies) but after swaping it out I still have the problem.

I can start it up (after sitting all night) and let it idle for a good 15mins and the gauge will be stuck on the bottom. I'll drive it about 10 miles to work (through a lot of downtown stop and go traffic) and by the time I get there, the needle will still be resting peacefully at the bottom of the gauge. My heat (interior) seems to be working fine, btw. The only way I've managed to get it up to halfway on the gauge is by letting it sit and idle for 20mins or so after I've driven a good 15 miles or so.

I was about ready to try the temp sensor, but now I'm wondering anything's wrong with it? I've read in the archives that it'll throw a fault code if it's bad. Would that mean a SES light on my dash? (Which I don't have.) Or could a fault code be in there and the only way I can find it is via that diagnostic gizmo in the engine compartment?

Please throw some ideas at me. I'm at a real loss on this one. Thanks.