Spark plug NGK or Motorcraft

My 2017 Jetta SEL with LFER7BHX 9512 plugs starts/runs fine at 50076 miles, 0-100 degrees F.

You can run NGK Rutheniums, i run them on with my is20 and no complaints either.

I swapped for Rutheniums, No complaints and its a easy job

Stick to NGK R7437s. They are pricey but the best plug for a tuned car forsure. I inspect the gap every 5k miles and replace every 10k. Mine are gapped to .022

I’d go with the recommended NGKs, buy from fcp euro and you only need to pay for them once. Those are what I run on APR stage 2.

I went ahead with an NGK Laser Iridium. Compared the ones from the engine and the new ones and were identical in shape and form. It does seem to work fine after testing it.

NGK Iridium, it’s what I get about everytime.

Recently got the following parts: Racingline VWR Springs 034 Motorsports strut mounts, new bearings and bump stops Rear strut mounts with new hardware and bump stops Deautoled LED license plate OEM Autodimming rear mirror with wiring harness APR boost tap NSP boost gauge with vent Hella oil level sensor Oil pan w level sensor European Headlight Switch APR Coilpacks Spark Plugs NGK BKR8EIX R LINE CENTER CAPS

That’s curious….. if you look closely at the end of the shorter plug you can see another set of threads, it looks like there an insert threaded onto that spark plug. It would appear that it wouldn’t be sitting where it needs to in the combustion chamber so that may explain your misfire.

I've had my 2006 Audi a3 3.2 quattro dsg for 5 years now, and every year or so I will have an issue with a misfire on cylinder 6. It is always cylinder 6. I use the recommended NKG IZKR7B(7563) plugs. I often find that the cylinder 6 plug has a crack on the ceramic insulator around the electrode. On one of the plugs, half of the insulator is missing. Replacing the plug always fixes the misfire. I also noticed most recently when I removed the damaged plug, it was very hard to turn and some of the aluminum from the head has fused to the threads, leading me to believe that the cylinder is getting too hot.