Spark plug OEM BMW or AC DELCO

I did absolutely nothing apart of spark plugs and oil change . I had E90, 188k km, 330d until it meet it's end when I crash it to railguards. it never showed me any lights or anything so I would say around 60-80$ tops.

Believe it or not I got the Genuine AC Delco iridiums from Home Depot for $3 a plug.

I almost went 200000 km on my bmw between spark plug changes, and the motor runs so much better after. My fuel economy almost doubled, and performance was a night and day difference

Problem solved: I got a internally bad ac delco spark plug. Gap and everything was correct no cracks I could see literally just a bad plug.

I bought my 2019 330i in 2022. It was a lease return. While basic maintenance items are a lot more than, let’s say, a Toyota, it has been far from a money pit. I have put 50k miles on it in the three years I’ve had it, and had nothing out of the ordinary go wrong. Spark plugs, brake pads, air filters, tires, oil changes, that’s it.

I did my spark plugs on my 335i f30 and I can say one thing. $400 for labor on spark plugs is treason. Shit should take those "experienced" mechanics maybe an hour.

I recommend nothing with platinum. I've had problems with those in my 1980 gbody with a 305. I just keep it simple with old ac/delcos now. Keep it simple for less problems.

Problem solved: I got a internally bad ac delco spark plug. Gap and everything was correct no cracks I could see literally just a bad plug.

I dug factory installed spark plugs out of my recently departed E90... they looked like something from the stone age. 19 year old car, and from what I could tell, never had the plugs changes.

Cylinders 1-3 were misfiring. They couldn't get the spark plug out of cylinder 3 because the other dealership had over tightened it. They had to get a special tool to remove it. The tool BROKE because apparently it was so overtightened and mis-threaded. They finally got it out yesterday and sent the cylinder to the machine shop to get the head off. I just got word that there is a hole in the piston and the valve head is completely gone. They are saying now that it has nothing to do with the spark plug being overtightened. He asked about driving through water, and road conditions. It was a dry day. Not an issue. They said I need a new motor at this point.