Our faithful 96 A6 Avant 2.8L failed smog check, not because of the Smog limits, but because of the oil burning smokes and blue smoke coming from the engine bay and the exhaust pipe. The smog technician insisted that the smokes come from the engine bay is the crank case leaks, although we could see the oil is leaking from the valve cover gasket and drips to the exhaust pipes. Anyhow, it failed the visual tests and I had to fix the “crank case leaks” and the blue smoke coming from the exhaust pipe.
I got the gaskets from autohausearizona (easy return and fast shipping).
Remove the engine cover, 4 screw driver spring loaded nuts, the right side is where the oil leaks the most, I started there. Remove all the hex bolts holding the valve cover gasket. We do need to remove some electrical wirings on top of the valve cover also.
Yes, the gasket was totally brittle and break off when we lifted the valve cover up and out. We clean the gasket channel and place a new one in it, press it down all around and completely in.
Clean the head surface before putting back the valve cover gasket, I did put some oil on the rubber gasket surface prior to installation (just like putting oil filter back). Remember to torque the 6 hex bolts evenly (diagonally) and slowly one by one.
While I was there, I remove the gas butterfly to clean it also, it’s amazingly dirty.
Carburetor cleaner and brushes to get all these gums out, the the car runs so much smoother with great idling.
Now, to get rid of blue smoke, I replaced all spark plugs, it’s amazing that my A6 is still running, the center electrode is worn off totally.
Replacing the spark plugs is straight forward, just need long extension, tape the spark plug socket to the extension (so it won’t get stuck with the spark plug when we install the new one).
I oil (I’m obsessed with oil) my spark plug thread before insert it into the socket, use hand to turn the socket to make sure the threads are in correctly, no stripping.
After everything is done, the smog technician was so happy to pass the smog check and I thanked him for forcing me to check the spark plugs, they’re pretty bad and it just shows, worn out spark plugs still starts the car right up, drive normally although the performance may be degraded, but I didn’t even noticed. What a faithful Audi.