Spark plug NGK or Denso

Also you might have bad type of plugs - NGK PFR6T-10G is correct one.

Yes, all the time. No big deal!

The CX5 should not be a problem. All the posts telling horror stories aren’t answering the question. You don’t need to be ripped-off by a dealer for this task. You must have a Friend or neighbor to help! It’s a 30 min job at the most. Be sure to get the right plugs, NGK is a great brand.

I’d personally run NGK, they have always performed better than Bosch in these generation engines. Iridium if possible and just whatever my reputable local parts supplier would get me.

I'll just start with my bias of never using Denso for anything anymore but for plugs I only use NGK laser iridium and always get at least 80k out of them.

Should have used NGK Laser Iridium plugs and Hitachi coils.

Mazda skyactiv engines are beyond easy to do. Did it on my 16 Mazda6 in 20 minutes. Probably can be done sooner if the spark plugs are pre-gapped and you're not OCD.

Did 3 of the 4 of them on my wife's CX-9 and it took way longer, due to the turbo parts on top and the engine being set, so far back (vertically challenged and T-Rex arms). Dealer ended up doing the 4th one (driver side plug).

Rock Auto has good deals on the NGK plugs, that are basically the same as the OEM ones.

Torque wrench is unnecessary for plugs. I have several and have never once used them for plugs. 1/4 turn past hand tight is all you need. Good plugs like ngk laser iridium or ruthenium hx will run you less than 40 bucks. A small single use packet of anti seize compound and a 6 pack of your preferred beer. Less than 100 bucks all in and an hour of your time.

I do NGK 6510 one step colder. I do 0.025”-0.026” gap. I had a shop do my last set since I didn’t trust myself. He accidentally did 0.022” and I put them in and they’ve been fine. The other set is 0.018” and idk if ima put them in. Gotta change the one step colder NGK’s at around 15-20k miles. I usually change mine when I start seeing high spark retard. I’m BT 93/E40 with aux.

I bought 2 sets of NGK Irridium plugs from Amazon sellers that turned out to be counterfeit. The electrodes were completely worn off with 60k miles on them. They are supposed to last 100,000 miles. The cars were misfiring and had spark knock.

I learned that proper, very hard to tell, NGK knock offs even existed after I was bitten by fake ones off Amazon. The porcelain around the center electrode broke off and went through the engine.