Pretty new to audi forums ... maybe someone can help ...
A4 B6 ... I had replaced no. 4 ignition coil in the car, thats what the diagnosis said and it was right, my engine light went away. Then ... 2-3 months later ... engine light came back on ... reading some stuff ... i end up buying vag 405 that told me there was a sparatic fire on cylinder no. 4. To test it all out ... I swapped ignition coil no. 3 and 4 around ... did the vag test and came out that it still kept the original code as I did not clear the codes before hand but also said it was a multiple misfire ... does it mean that the ignition coild I just bought is GARBAGE???

Question about the vag 405 ... I am kinda scarred to do the erase code as I am thinking I may erase some othere stuff that may end up my Audi being programmed by the dealer ... end up in spending $$$ some more ... is that a possibility ... should I worry ...

 

you need to clear the code and if there is a problem, it will come back soon enough. If you still have the code you may have a bad spark plug, plugs torqued incorrectlyor the gap has grown. Also, make sure your coilpack isnt popping up.

finally, if you move the coilpacks and its still in cylinder 4, its not your coilpack

 

Clear the codes with VAg will be safe.

 

16684 P0300 Random/Multiple Cylinder Misfire Detected,
comes up with a single cylinder misfire.