Searching Google I saw some places say P0900 is the Clutch Actuator Circuit/Open.

It's an automatic, and there's nothing wrong with the transmission. It's definitely something with my fuel pressure system, just seeing if someone is able to pinpoint it before I go replacing things piece by piece

Take it to the dealer and have them scan it... That will be your best pinpoint

I'm guessing your Canadian, if you have ever taken your car to Midas (I go to them for an oil change once a year), so that they scan my car and look at it for free, tell me what the problem is then I go somewhere else and get it fixed..

Oil change once a year? Lol


What I am saying is, sir. Generic scanners are generic, the one your dealer will carry is much mote high tech and can look at any and every aspect of your ride and monitor it. Telling you how many misfires and what's causing it, low fuel pressure, not enough air, everything.
will cost you probably $100 or so, but you will know wtf is going on. Oh have them change that sludge too, probably isn't helping.

Interestingly enough, cylinder 2's spark plug went last night - 2 and 4 are the ones I put the same pack of plugs in, so unless 1 and 3 go, methinks I just got a bad set of plugs.

Anyways, in regards to fuel pressure up the solenoid (P0900), I'm going to replace the Fuel pressure Regulator first, to see if that clears the code, and the solenoid second.

just use copper plugs, 2$ each and change them every oil change. I have done this with every turbo car I have owned and it's worth it.

Yeah, realizing that, likely going to do that, especially since im planning on getting rid of the mazda in the next 6-12 months, just need her to run smooth as a day-to-day commuter.

yeah man, it's only an extra 8$ each oil change and makes the car run a lot better most of the time. Plugs get fouled so fast on turbo cars.

I've never had such an issue before, it's strange that it's happening now.