Hi,

I had my coolant system flushed and refilled and a new reservoir tank put in about 2-3 months ago on my 96 a4. Since then, I have had two times that my coolant has "disappeared" somewhat suddenly, dropping to the bottom of the reservoir and triggering the warning light. The first time was around the beginning of January, and the 2nd time I noticed was today. I'm not sure how long it took to go down the first time, but this second timeI had checked as recently as a week ago and the level had not dropped.Then, today while I was driving, I was getting no heat even though the car was set at 78 degrees.I bumped the thermostat up to max and heat started coming out, but shortly after that,the coolant level warning started going off and it is down almost to the hose in the reservoir again.

Does anyone know the likely cause and or tips to diagnose where it is going? There are no obvious leaks around the reservoir tank or that sort of thing. I understand that it could be a number of things such as leaks, head gasket, water pump, etc. but would appreciate any help in knowing where to start. I'm reluctant to take a car this old in to the stealership for a diagnosis just yet...

Thanks,
Brian

 

and you never find it on the ground?

 

sounds like maybe you've got a leak in your heater core...try blasting the heater full blast when the car is parked and see if you can see/smell coolant anywhere under the hood

 

If you dont see any coolant anywhere, then what you are experiencing most likely is air in the system, so you need to bleed it.

To bleed:

on hose connectiongoing into heatercore, near the windshield in the engine compartment, you want to loosen the (right side I think) hose clamp, and pull the hose back until you see the small bleeder hole. Then, unscrew the expansion tank and take off the cap. You will then hold or prop the tank up as high up as you can get it, so its higher than the hose you loosened. Then, you want to put fluid into the expansion tank, until you see fluid coming out of the small hole. Once fluid is coming out, push hose back on and clamp, and screw expansion tank back in place. The start the car, and make sure the fluid level is normal, and you should be in good shape.

 

coolant just disappears with no trace?? sounds like head gasket problem

 

Yes, It seems to be gone with no trace. Although I hope it isn't the head gasket... how could I tell if it was a head gasket problem?

 

white smoke mate from the exhaust

 

Hard to tell since it is winter here... everyone has white exhaust! I don't notice an excessive/different amount though...

 

check your oil and breather if there is white build up you got a toast headgasket most likely

 

white smoke from a blown head gasket will linger much longer than the normal exhaustsmoke in winter