Where is the water going when you have to keep adding water. The light in the car comes on & it is saying low coolant. Where could it be going? It is a 2003 VW Passat. thanks

This could be a heater matrix failure the heater matrix is situated just to the passenger side of the centre console under the dash if you have a wet carpet that is where I would be looking for the culprit of my water leak. hope this info is of use to you and please let me know how you get on with it

HI sorry for the very late response, i just got back from a trip. but the first three answers are steering you in the right direction. from my previous experience working on volkswagens they have a common problem with coolant leaks coming from the thermostat housing,(housing is made of carbon fiber material) it is located between the engine and transmission area, right above the transmission and under the air filter assembly. very hard to have a visual line of sight to it, use a bright l.e.d. lamp/light and look for water marks on top of transmission. (can be seen with the help of a small telescopic mirror) of course it would be a lot easier to take to a radiator shop and ask them to pressure test the coolant system. also the water coming inside to the passenger side floorboard and getting the carpet wet is from the a/c "evaporator" located behind the dash storage compartment, either the water drain tube is clogged or the evaporator pan is cracked, (made of plastic)

Hello! If the loss of coolant is slow there is a leak in one of the radiator or heater hoses...A pinhole in the radiator or recovery bottle...Engine heat will cause evaporation, so when you look for coolant/water it's gone...However, you should be able to smell coolant...With the hood open and engine hot look closely with a bright light for signs of a leak and use your nose to narrow it down...If the loss is internal (blown head gasket) here are signs to confirm: Overheating will almost always occur, due to the exhaust entering the coolant... Check your overflow bottle for exhaust smells... Watch for bubbles or overflow of coolant from the radiator while running the engine... Check for muddy gray-looking oil or bubbles on the dipstick.Often (but not always), a blown head gasket will also cause deposits of water on a piece of cardboard held an inch from the tailpipe output while the engine is running... Sometimes water will be seen dropping from the end of the tailpipe...

First check for internal leaks in the engine compartment,check all hoses and radiator. then check inside car for signs of leaks from heater,look on floor for damp..if no sign of leak take oil filler cap off and see if theres a dirty white froth of oil and water,this is one indication of blown head gasket,it could ,,also leak out of exaust if the gaskets gone,it could also be a cracked block,DON,T drive if its overheating.you are going to have to take it to a garage for repairs. sorry

You either have an external or internal leak. If you see no external leak that is very bad news and you more than likely have a blown head gasket especially if the engine has overheated recently. STOP driving this vehicle or you will do serious internal engine damage. Have it looked at by a professional immediately.