My girlfriends 1997 a4 is a 12v 2.8 quattro the car was throwing a random misfire code p0300 a while back and i scanned it again and it gave me p0300 again but this time in the description it showed cylinder 5, the weird thing is its not showing p0305. Any ideas whats going on? Ill also upload a pic of the code.


I just find it odd how before it only gave me p0300 random misfire and then i scaned it again a month later and it giving a more detailed description. Im going to start with the basic and replace the spark plug on cylinder 5 tomorrow and see what happens.

 

That's the best first move. On a 2.8 you can't really swap coils around like you can on a 1.8T. If the plug isn't a fix, try a can of seafoam in half a tank of gas. It could be crap in the injector clogging it up and that should help to clean it out.

 

Easier way to clean the injectors out is to simply crimp the fuel return line with block off pliers. The fuel pressure will shoot up and any crud in there should be blasted out.

 

Thanks for the feed back, i was thinking about swapping the coils between cylinder 5 and 6 and seeing how that turns out.

Thanks didn't know about that.