Coolant reservoir goes from Min to Max in 1000 miles

[jining]

111k miles on my 04 and I just realized that I am losing coolant slowly, the reservoir goes from max to min in about 1k miles. Must be a slow leak, as I don't see any coolant on the ground... What is the most common place to check? Hope it's not head gasket. Thank you.

[MidwestB6]

It's unlikely that it would be the head gasket
http://www.audizine.com/forum/showth...=1#post4049232

Are you always checking when the engine is hot? If you check it when it's hot, then again when it's cold, you will most likely get two different levels. As long as it's always above the min line, I wouldn't lose any sleep.

Otherwise, on the passenger side, between the air box and headlight is a series of hoses, there is a plastic elbow in there that may crack with age. Other than that, if you want to get under the car, remove the belly pan then look around the alternator, water pump, and aux radiators. If your feet are wet you could investigate the heater as well.

[SAILSMAN]

I would look at the tank at the bottom where the lower hose hooks up as I have had the tank develop a hairline crack and when the engine is hot the coolant merely evaporates after hitting the hot valve cover making it difficult to determine a leak. I found the leak on mine as a bit of residue was left on the valve cover and on the lower hose.

[emilio]

do you smell coolant in the engine compartment after a good drive? can you also smell it in the wheel well and around the front door sills with the engine compartment closed?

i also had a crack in that elbow with an offshoot near the airbox, which may have been a very slow leak. after replacing that part and another coolant hose (heater core return, iirc) i noticed that these black plastic heater bits start to get very brittle and discolored after >100K miles. check for moisture around all the hoses you can see, especially around the connectors and any cloth sleeves (which can hide leaks).

- emilio