Spark plug Bosch or BRISK

Stock is generally fine, however if your tracking or going through multiple heat cycles on your drives id recommend er12s from brisk. I run them and they havent skipped at beat. Intervals are shorter for changes.

It doesn't look eroded. It looks like the centre electrode tip has fallen off. That shouldn't happen. I usually only use Bosch or NGK plugs. I've never heard of Auto lite...

August 28 2024 : Spark plug change Bosch 70,588

I run more or less the same motor (2.1liter-276 Schrick-10.5CR), and I'm using stock Bosch spark plugs.

Your observation is correct.

Bosch is the original manufacturer. Buying from them will be cheaper. Mercedes genuine just means they take the Bosch part and slap their name on it to say "yes, this component is up to our standard".

Changed valve cover/gasket and installed new Bosch plugs and NGK boots.

Car had slightly higher rpms at cold startup but didn\u2019t think anything was wrong. After a few days engine started to misfire. I did some research and it sounded like I should use OEM plugs. I purchased Nissan plugs from the dealer and replaced the Bosch plugs. Misfire went away, but higher rpms at cold start persisted.

I recently took my stage 2 43K mile b8.5 s4 apart and did the PCV, water pump, thermostat, new 2 step colder brisk spark plugs gapped to .25. I took the spark plugs out and noticed heavy carbon and the ground electrode was white, even on all plugs . (20 miles on plugs)

I have a 21 xlt 4wd 2.7 and I do A LOT of driving for work. Recently crossed 80k miles and it started misfiring like crazy shortly after that and threw a code. Pulled the plugs and they were definitely fouled. I did some reading and saw most people change the plugs out around this interval so I went ahead and did it. EVERY auto part store near me only had 1 or 2 oem plugs and I couldn\u2019t really wait so I went ahead and got BOSCH iridium plugs. Well I\u2019m noticing when I get on it or go to speed up at higher RPMs/gears, I\u2019m getting what feels like stuttering or very minor misfires every now but it\u2019s not throwing any codes.

NEVER USE THE DEALER FOR REPAIR WORK!

If it is the skyactive-x be aware that the owners manual advises spark plug replacement at 40k miles and the Mazda plugs are \u00a340 each. I put aftermarket Bosch plugs in and it ran very lumpy and had to replace with Mazda ones.