Originally Posted by bmwpk
Awesome write up. How did the car feel afterwards? My 330i has been idling funny. I cleaned maf and just put in new spark plugs, this maybe my next step.
Smoother idle, smoother from 2500-4000, with a less gruff sound. Acceleration feels a just little more free. I had thought my engine was aging well, but in the week or so after I used this I realized that I had simply become accustomed to very slightly degraded performance. None of the changes were huge, but it was worth it.
Also, since I ran it through my crank case (a few weeks before I did the above tutorial) my mileage has improved. This hadn't happened in previous cars I'd Seafoamed (indeed, my truck actually had decreased
mileage), but I'm getting maybe 5-8% better mileage on the highway. I don't have a large enough city sample to say anything on that, but in a couple of lengthy highway drives I have really noticed a difference. I expect this to be temporary, and, literally, your mileage may vary, but that's the experience I've had since Seafoaming. I also changed the plugs, so that undoubtedly has something to do with it, but I'm getting better mileage than when the car was new.
2008 328i, Black Sapphire, Sports, Premium, AT with the flappy paddles