killert

Hi guys, need some help figuring out a problem with a fairly big amount of coolant leaking from the front end of my car. I noticed the coolant wont leak out as the car is turned on but as soon as you shut it off it leaks a pretty good amount then stops leaking after some time. I tried to find out the problem by lifting the car and noticed some coolant under the radiator, but cant see if its actually the radiator causing it to leak. It flows from that area then down the front bumper and finaly to the floor. the car is a 99 a4 2.8L Q.

any ideas on what the problem might be and how much it would cost???

ANY HELP WOULD BE APPRECIATED THNX

K04-S4

G12 coolant leaks pink and flakey white-ish track marks. Need to inspect under hood and / or under the front end as there could be several possible sources of the leak.

One fairly common issue is the Coolant Expansion Tank turns brown and goes brittle with age, then cracks and noticably leaks when coolant system is pressurized up to operating temp.

killert

Where exactly is that tank your talking about? lower front end of the car??? anyway i took the car to canadian tire and they didnt have the tools to do a pressure test, but the mechanic there told me that hes pretty sure its the radiator. Im not sure if hes right or wrong. and i dont want to go buy a radiator if thats not it. Im beginning to see that sometimes you just have to take it to audi but **** that sucks

K04-S4

Lift the front hood and have a look for the ~1L sized white (or aged brown) plastic coolant expansion tank with the palm sized blue screw-on cap.

Again, a thorough inspection to source the leak is required. It's a bit of labor to replace a rad so you want confirmation before purchasing parts and opening up the cooling system.

Coolant Expansion Tank looks like this:

whoace

Don't take his guess at it. It could be something as small as a hose and you would have just replaced the whole rad. Go to a place that can properly pressure test the system. You don't necessarily need to go to the dealer. Go to a european specialist or an independent shop. Most shops that work on all makes and models will carry the adapter for the expansion tank.

K04-S4

The advice is to perform a visual inspection as this can be sufficient to find the source of rather obvious G12 leak track marks. Of all the fluids in the vehicle, G12 is the easiest to visually trace leaks. If not possible to trace leak visually for any reason, then a coolant system pressure test is in order.

The "guess" was to inspect one of the more common coolant leak sources. If not replaced already due to failure, the expansion tank only takes a few minutes to visually inspect for cracks and G12 leak tracks. Checking the expansion tank is generally recommended to be part of the overall coolant leak inspection process, especially if the plastic tank has turned brown.

If I work on an Audi and see a dark brown tank, I generally advise the owner of the issue so that they can consider replacing it for reliability purposes during any future coolant system work. Replaced my '01 S4 dark brown $50 tank along with a coolant flush at 75K KMs for this very reason.