[davidk]

I have a 2018 factory stock OG M2, no mods. I currently have approximately 12,000 miles on the spark plugs. They were last replaced four years ago at 15,000 miles using the BMW free maintenance program. My SA keeps wanting me to replace them because BMW recommends new plugs at every third oil change. The car only has 27,500 miles on it, no track use. When should these plugs be replaced?

[Coupsoup]

The 'normal service' maintenance chart calls for plugs every 30k. If you are easy on the car, it could qualify for 'normal service'. However, most drivers of performance cars operate them under what is considered 'severe service' conditions.

It is not unusual for specialists to tighten up maintenance intervals based on their experience and observations during repairs. Considering BMW oil change intervals are way too long it is likely the '3 oil changes' is approximately 22.5-30k depending on the specific shop.

[E90convert]

If you're not tracking the car, go the complete 30K on the plugs and not worry about the time interval. The intervals on an M-car presumably would have some track time built into the maintenance intervals. The M235iR has 5,000 km spark plug change intervals, but no time interval exists. That is nearly 100% competitive racing mileage.

[davidk]

Thanks for the replies. I thought it was 30,000 mi, but wasn't sure. The car is "exercised" from time to time, but 12,000 miles plug change interval is a bit overkill.