Spark plug Bosch or Champion

My 2017 VW Jetta 1.4 5M - at 67760 miles on the factory original plugs - now has new Bosch Iridium/Plattinum plugs - (YA5KIP80)..................(the only symptom on the old plugs was a MPG drop - no hard starting, no missing, no rough idle......... EZ

Stick with Champion plugs in the 4.0L inline 6. Anything else will have you chasing a “stumbling” idle.

I use champion on my 04. No issues. The more expensive ones that’s when the issues start

I use Champion in my 02. Never had any issues.

I learned this after installing Bosch plugs in a Honda many moons ago. Japanese cars like Japanese-designed plugs.

Ja tive problema com velas bosch. NGK é melhor.

I tried Bosch plugs on a 1995 NG900. Problem as described. When they state compatible, that might only address mechanical fit. Stick with the original plugs

My service center guys installed Champion plug instead of Bosch on my turbocharged Altroz. Company user manual clearly says to use Bosch in TC. My car's economy has dropped significantly...and I'm just frustrated.

I won't run champion plugs in anything but lawn mowers. That's the only thing I've put them in that didn't get angry about it. Guess everybody's vehicles are different, but personally I don't think they're very good plugs.

I personally refuse to put anything Bosch made in my cars. All were genuine Bosch parts from my local parts place that has never done me wrong.

First it was their wipers, paid good money for them, squeeled worse than the worn old ones. Figured it's a fluke.

Then I had a set of spark plugs, they were gapped correctly, but the car ran like absolute garbage and I couldn't figure it out until I put the probably 20 year old Valeos back in and it ran fine again.

Then I had a crankshaft sensor that was bad out of the box, and that was the last straw for me. I don't care if it's coincidence or a bad batch, or if they've improved it since, I'm done with any Bosch parts unless it's NOS from the early 2000s or earlier.