heys guys. so i scanned my car this morning and i am getting the code p0303. i have had this problem previously and it was the icm causing the misfire on Cyl. 3. but that was like 9 months ago. could the icm have gone bad by now? or could it be something else? i did a search here and i saw a list of things, sparks, cat, coils... but is there any real way to narrow it down to one solution?

98 a4 1.8t

thanks

 

coil pack or bad spark plug

 

Swap coil #3 with another. If the P0303 comes back, swap spark plugs.