Hey guys. I have a 2000 A6 2.8 quattro (avant). Recently (the past year or so), i have noticed that the coolant and oil temperature gauges have been acting funny. When i drive the car it warms up and gets to full operating temperature (coolant gauge right in the middle (12 o'clock)) and the oil temperature gauge is at the 175 degree mark (i believe, im not positive, i have to check to be sure). If i stay on the gas or do around town driving, they always stay this way. However, when cruising on the highway or coming back home through Penn state and let off the gas (coast) down a hill or whatever, they drop. It seems the more i coast, the more they go down. ( the lowest either has gone is abit below the third mark on the coolant and at the second mark for the oil). I thought this was a bit weird, but then thought that without a load on the engine and with a good amount of air flow through the rad, it might do that. I do not remember it doing this a year or two ago, or maybe i just never noticed. Another thing i found funny is when i engine brake, it does the same thing. I searched a bit, and it seems that most said to replace the coolant temp gauge, but what about the oil temp gauge? Could it be anything else? Thanks for the help.

 

anyone?