1998 a6 quattro 2.8 v6 has a check engine light on. Brought it over to autozone. Error code #p0306 came up.
The only thing I have tried so far is change the number 6 spark plug and disconnected the battery for a good 15 minutes. Started the car up and the check engine lights was on from the start. I'm not sure if disconnecting the battery reset the ecm at all.
I'm looking for a few suggestions on the steps I should take next. Is there a way to test the coil pack to see if it is sending a spark to the plug? Which o2 sensor I should check and how many o2 sensors are there? Any help is appreciated because I'm looking to do this myself.

 

ok just researched and found out the disconnecting the battery wont work

 

go back to autozone and use the scanner to erase the code...

 

Most of them won't do it - they're subject to a $10,000 fine for doing so.

 

Not sure about your specific car, but I had a misfire code and checked plugs, coils, and eventually led to the ignition control module being faulty. Not sure about the 2.8L but the 1.8T did and After I had it tested and replaced it, it got rid of the misfire instantly. Just something to look into