Spark Plugs. The heck you say. . .

[Giznaz]

So, the black beast was getting worse gas mileage, and backfiring/missing/hesitating/coughing (insert adjective of your choice) below about 1500 RPM's.

The ONLY cure was a bottle of Techron in each tank of gas. This was with using Top Tier Premium gas.

Well, I finally had some time to wrench on it, and spent New Years afternoon replacing the spark plugs.

Well, so far, that has fixed the issue! No more (insert adjective here)!!

Gave the old ones a thorough visual inspection, and didn't see anything out of the ordinary. Deposits and color were good. The only thing that might be out of spec is that the center electrode was inset into the ceramic a couple thousands more than the new ones. As far as I know, 101K miles on the plugs..

So, all is good again!

[civdiv99]

Whadcha decide to use brand-wise?

[Giznaz]

I got the OE BMW ones. Only issue was they were Bosch. The NGK and Bosch are unusual in that they carry the exact same part number. Usually the same part from different vendors have a slightly different part number.

In this case, it wasn't true. The "Made In" label is the only diff.
The dealer only had 3 Made in Japan's, and 20 Germany ones.

Was costly, but I didn't have time for mail order. . .