[IIMisterII]

Hello,

I am having an issue with my 650i GC with the spark plugs having to be replaced every few months. I'll be driving fine for awhile and then all of a sudden I'll get a misfire and get the DTM error and a code for a certain cylinder misfire. Once I replace the spark plug for that cylinder and clear the codes, all is well. But then a few months later it happens once again in a different cylinder, and this repeats over and over.

Fine for a couple months > Misfire > Replace that cylinder's spark plug and/or injector > Fine for a couple months > Repeat.

I'm not sure what could be causing this issue as this is my first BMW and I am new to this. I tried searching up on the forums for an answer but the problems people encounter similar to this have varying reasons as to why they're encountering them.

As a note, I have BM3 Stage 1 on 91 Octane (shitty gas where I live) and the car only has 56k miles. I had originally replaced all the spark plugs and cylinders with the NGK Iridium 1-step colder plugs before I put the BM3 tune on the car at 48k miles.

The only reason I could think that could be causing this would be either an issue somewhere within my fuel system or that I gapped the plugs incorrectly when I first replaced them. I originally gapped them at 0.022, as that was the recommendation from BM3, but now I'm thinking maybe I need to go up to something "safer" like 0.026?

Again, I'm not sure as I am still new to this car.. Any suggestions or comments would be helpful. The car's great when I'm not having misfires, but to have to deal with them every few months is a pain and the cost adds up fast.

Thanks