Report "Hi all. I was wondering if anyone has experienced this. We have a 2003 MPV that suddenly started running colder than normal. Usually the thermostat shows the needle right in the middle of the guage, but now it's halfway between cold and the normal middle area. After a couple days of this the check engine light came on. We took it to the shop (not Mazda) and they said it was the thermostat and replaced it. The new thermostat produced the same results (still cold). So they thought maybe they got a defective one. They put an actual Mazda thermostat in there and said it worked until the drove it on the highway and it went back down to the cold area. Now they think it might be the water pump impeller sheared off so they're checking that. Ugh, does anyone here have an idea as to what's happening? Also, it is chilly out, but not that chilly (40 low, 60 high). Thanks! Dave"