P1315 P0303 - swapped coils, new plugs, problem still here
 

Hello -

I have a few codes on my 986 that i'm trying to diagnose. P1315, P0303, and P0506, blinking CEL.

I have put a new air filter, new oil, new spark plugs, new off brand ICV, used working ICV, and swapped the coils. The codes persist.

I'm a bit at my wits end here. Any advice on what next? I'm trying to do a suspension overhaul but am having trouble passing smog for this.

Thanks in advance

I think you're on the right track, maybe consider the injector(s)? Just to be clear, cylinder 3 is on the far left when looking (at bank 1) from the passenger side...
http://986forum.com/forums/uploads02/bank1730564899.jpg

It ended up being a disconnected coil pack 🤦****♂️😂

Replaced them anyway and all good

But the feeling of having found it is unbeatable!