E39 540 Misfire..........help

[paul540/m3]

I know this isn't an M5 question just wondering if I could get some general E39 help.
I'm having some problems with my car, the check engine light is coming on and when scanned the code reades misfire in cylinder 2. My mechanic switched plug one and 2 and the light went away for a bit but then when it came back on a couple days later it read misfire in cylinder 1 and 2. The light seams to come on when I take the car to high revs like 4k plus. I'm thinking I need to change my plugs and wires. I guess it's about time, 70k km right? Anyways my question is what is available in terms of plugs and wires for this car? Are there any aftermarket upgrades I should be aware of or just wtick with OEM? Any disadvantages with aftermarket products?
Thanks in advance.

[6spd]

Paul you don't have any plug wires on the car.
The coils mount on top of the plugs.
Change out all the plugs and swap the coils from side to side and see if the error changes sides.

[SWildung]

My previous car was a 540i and would also throw the same code on occasion, I noticed that is was most common when running poor quality, lower octane fuel and/or when not allowing the car to warm up before .

[bmwdctr]

Originally Posted by 6spd

Paul you don't have any plug wires on the car.
The coils mount on top of the plugs.
Change out all the plugs and swap the coils from side to side and see if the error changes sides.

Bingo! Common problem. Great method to find the exact coil too But you don't have to open up the other bank, simply change the coil(s) in question with another one.
-D