Reviews of Bosch spark plug

at 100k km, I replaced (all Bosch) Plugs , Coils, starter, battery, voltage regulator (40).

So new Bosch plugs and red-top coils seemed worth the $109. Old spark plugs were pretty crusty, which made me feel better about doing it.

FWIW, if you don't have Bosch, BERU, Bremi, or NGK plugs/coils and have store brand stuff, I stop diagnostic work until you get OE grade stuff put in there. BMW's don't like the Zone/ebay for ignition parts in my experience.

Yeah can go wrong with acdelco. I run Bosch in my 93 4.3

Yeah I own and operate an auto repair facility and refuse to use Bosch plugs because I’ve had a lot of issues with them in the past. Misfires mostly.

I've heard for many decades how bad Bosch spark plugs are and I figured the coils would be just as bad, if not worse.

I've run Bosch iridium's in all my vehicles (boosted and daily). No gapping needed.

Bosch spark plugs are junk.

This is why I don't use Bosch plugs. It goes back to the quad fire plugs with a platinum center electrode that would fall out.

Long story short: changed spark plugs 4000km ago as per my 2019 Hyundai Kona 1.6t manual. Followed Service manual, and the recommended torque on the side of the box of the Bosch (non OEM) replacement, 17 ftlbs.

Grounding electrode on plug #3 failed, destroying 2 valves and marking up the cylinder wall.