Spark plug NGK or OEM Subaru

From literally every single objective comparison, the NGK ILKR9Q7G looks like be identical to the HKS M45XL except for price. NGK literally produces the plugs for HKS and NGK is likely the largest plug manufacture in the world with decades of reliable products to boot.

Mine are either ACDelco or NGK, cant remember which. Either way no complaints.

I went ahead and replaced all 4 coil packs and plugs as well as the PCV valve. Since I have to order parts, it seemed faster than checking the plugs and swapping coil packs, as well as good insurance, since the coil packs and PCV valve were (over)due for replacement anyway. It took about an hour without rushing. Took about a 30-minute test drive, highway and town, and the engine's running smoothly. Ran a scan when I got home, and no new fault codes, so I cleared them all out and the check engine light went out.

I have always used double plat or ngk laser iridium with no issues in my 2.5.

I ran stock plugs for a while and they got chewed up fast. On NGks now and even pushing 29 psi they keep the gap well.

I run the IS38 FBO and beat the crap out of my car and use stock heat-range Rutheniums.

Spark plugs. NGK 4 lyfe

NGK spark plugs are preferred in rotary engine (RE) Mazdas and Nippondenso is the only acceptable substitute that I ever found. We dealership technicians, always found it remarkable how a set of Champion or AC spark plugs could instantly cripple a rotary powered Mazda.

I've used Autolite plugs in my stock 2011 for 6 years. I wanted to try NGK's so I recently installed a set of Ruthenium NGK plugs. I haven't noticed any difference between the two brands.

I also just put in a set of NGK BKR7E's and gapped them a little large (.034) seeing as the ones I pulled out were at .043 That did nothing and the issue is still persistent.