Hey, I bought a 98 A3 2 weeks ago i checked it out and everything seemed fine
But yesterday i started hearing a clicking sound similar to what you would hear if you put a piece of cardboard into to the spokes of a turning bicylce spokes! Had this looked at this morning the mechanic put it on a jack and told me he thought it was the cv joint gone, we took the it off the jack and i decided to go get a second opinion driving off i noticed the sound was gone!
Later though a big cloud of smoke came out of the exhaust and the engine started losing power and the car was shaking got the car home asap and had a look under the bonnet checked the oil dipstick and found yellow gunk similar to coffee on the stick i heard this is a head gasket gone but not sure was told to check by filling up the radiator fluid with water when the engine is cold and start the car with the cap off and see if there is constant bubbles but no bubbles whatsoever... also i heard the gunk could have came from condensation in the engine block as i only do short trips to work and it is freezing here in the winter! any help would be appreiciated! Sorry about the essay!!

 

sludge?

 

the stuff on the dipstick is a mix between water and oil i think..

 

That would be it...

 

If you do lots of short trips, you will definitely have "the sludge". This is not healthy as it can cause internal corrosion to the engine and premature replacement of the exhaust system. It takes about 30 minutes of running to burn off all the condensation.