My 2009 Infiniti G37x Sedan is throwing a P0300 (Multiple Misfires Failure) and P0302 (Cylinder 2 Misfire Detected) and kicking/stuttering pretty hard in idle, plus misfiring when accelerating. Mileage = 176K

My plan is to:
1) Clean the MAF Sensors
2) Clean throttle body
3) Replace all 6 Ignition Coils (OE 22448-EY00A from Z1 Motorsports @ $350 for 6)*
4) Replace all 6 spark plugs (OE 22401-JK01D from Z1 Motorsports @ $108.34 for 6) - haven't replaced any of these in ~100K miles

*I know the P0302 code targets Cylinder 2, but I'm thinking if they're all out and one is starting to fail, then probably best to replace them all?

Am I missing anything here that I should clean/replace? Am I buying junk parts?

 

I had only a P0300 when doing a engine overhaul. It was the fuel injectors. problem was a lot of components where changed and it was difficult to determine which item was the issue. I made the very BIG mistake of putting cleaned OEM injectors in. Place gave me a faulty set and of course played stupid and did not honor a return, typical eBay seller pedaling junk. I put my original ones in with new upper and lower O-Rings and clips and issue was resolved.

I used NGK spark plugs and coils for mine and had no issue with those.

 

I'll probably try to avoid fuel injectors for the time being because I'll need to take it to a shop to have those replaced. If I do have to go this route, is there a reputable site to pick up 6 of them versus paying dealership prices? They'll get their cut with the labor.

 

I understand, you will need to or have someone check what it might be.

I would not buy really any parts from the dealer. Get them from Amayama, Partsouq etc. A lot of times the parts are much cheaper and no tax, plus the shipping can be very fast. The shipping plus part cost most of the time makes getting things from the dealer irrelevant, unless it is a very large or heavy item, or if it is simply not available overseas.

https://www.amayama.com/en/part/nissan/16600ey00a

I believe you need: 16600-EY00A which is a Denso injector. Beck and Arnley I believe sells the actual Denso injectors as well, just re-boxed: https://www.rockauto.com/en/moreinfo...t=6224&jsn=730

BECK/ARNLEY 1581556 (16600-EY00A)