This is in my 2002 Legacy four-banger.  The short of it is that I've changed the plugs (new NKG, gapped at 0.044), new plug wires (NKG again), and swapped in a coil from a car that didn't have this particular error, and still I have a consistent po303 and po304.  omegle discord xender

When this started, I had misfires on all four cylinders.  I checked the plugs, and they looked awful, so I put in new plugs.  All was well for a day or so, then the problem came back. 

I swapped in a coil from a 2001 Impreza which was a good runner until its head gasket went.  All was well for a day or so, then the problem came back. 

Then the new wires arrived from Rock Auto, so I put them in.  All was well for a day or so, then the problem came back, but now it's only cylinders three and four that are misfiring.  

I'm starting to think I have some non-ignition problem which might be intermittent.  What should I try next? 

Edited April 15, 20205 yr by SolomonShawn

Check your timing.

O.

If you haven't already, I'd read this: https://forums.nasioc.com/forums/showthread.php?t=2318069

Fuel injector replacement isn't that difficult or expensive, might be worth a try. I bought a set of reman OEM injectors for my wrx from KM Racing on ebay. They seem legit. I think these are the right ones for your car, but you should confirm that:

https://www.ebay.com/itm/4x-OEM-2000-2006-Subaru-2-5L-NA-Fuel-Injectors-Flow-Tested-Cleaned/153500205940?hash=item23bd534374:g:HJIAAOSwLnBX7tXg#viTabs_0

Good luck!!!