Spark plug NGK or Denso

Denso itv20 (5339) for stock/mostly stock. ITV22 (5340) step colder if more mods. I have only used itv22 since 2015.

If you’re asking about brands, I always go NGK. They’re definitely my preference. They have a coating on the threads and don’t require grease when you install. And they come pre gapped.

NGK !!!

I went with Denso's on my 1.8T because that is what I had on the shelf. but I have ran anything and everything in vehicles over the years, and found that there is not much different between the different types.

Next day guy at the auto parts store tells me to try ngk iridium’s and it works automatically. If you’re planning to replace your spark plugs save your self the time and money and buy ngks over anything.

As always, go with NGK or Denso plugs.

My car was fitted with Denso Power when new, 11 years ago. It has done 63K Miles (101K Km, way more than the data sheets above say) and the economy continues to improve

I replaced the plugs again (from Brisk to NGK R7437-9) and rotated the coil packs to try and resolve the misfire issue. I also re-flashed both the ECU and TCU tunes, and the cold start misfire issue appears to be fixed.

Try changing out the rs7 plugs and go to NGK R7437-9 or 8. I’ve heard the RS7 plugs having issues in these cars.

If these are for a TJ (97-05) return them and get NTK (NGK). The 4.0 will not like anything else.