Hi all , not new to audi ownership but new on here and for a first post a request if possible for some help...
Hit a nice size pothole last week and took out two rims and shredded the tyres and whilst up on the jack changing them all over for new ones, went to top up the coolant and noticed I have some wonderful black sludge oil based in the header tank ...first worry was hgf but ...theres no loss of power, theres no excess smoke, theres no mayo on the oil cap, no froth on the dipstick and the sludge although black and oily doesn't "mayo" up ...my only thought is that this is somethign to do with the aircon as I can't think of anything else ...possibly co-incidence?...when I ventured into the pothole the bottom of the car ground nice and heavy and left a small hole and gouge in the bottom section of the bodywork right under the rads ...would this have done anything?...at a loss to explain the "sludge/oil" no any ideas would be appreciated greatly ....ta
Nick

 

Unless you have topped up the coolant with non-OEM "green" antifreeze, the most common cause would be a leak in the oil cooler allowing coolant and oil to mix.

 

Thanks David...I'll have a look or get it checked, as a long shot would or could this be related to the pothole I hit or just co-incidental ?...thanks again.
Nick

 

it could easily be a pin hole in the oil cooler caused when you hit the pothole but if this were the case the cooling system would boil over and you would loose coolant so I guess Dave has this in the bag and its just residue in the coolant system which was freed up when you hit that pothole

 

Thanks guys, the car is running ok which is the main concern so I'll have the coolant system flushed and see what happens thereafter, thinking about it I may have added coolant (non oem) I used some pre mixed that I had spare from the EliseI'm thinking this is green stuff...so maybe thats the answer ...thanks again for the help so quickly.