[The Nerd]

I have a 13' 335i with 2500 miles and an MPPK install and I'm curious if its normal to have carbon soot splatter up onto the bumper. I ask because, it's one thing to have soot build-up on the tail pipes, but quite another to have so much that it splatters up onto the rear bumper. For what it's worth, I only run 93 octane Shell and I've only noticed the splatter for about the last 500 miles. I know direct injection engines create a lot of carbon....but did my car mysteriously start running richer 500 miles ago? Or...maybe this is normal?

My other concern is that, if I'm running too rich, I'm not putting out as much power. I swear my MPG has gone down slightly over the last 500 miles as well....haha, but maybe that's just me thinking about it too much!

Thoughts?

[belchwad]

Just recently noticed the same thing on my vehicle. My initial thought was that this occurs on all cars, but since mine is white I can see it better. One just doesn't notice on dark vehicles? I just started noticing around the 2500 mile mark. I don't believe I've purchased the same brand of gasoline since to be able to pinpoint it on a certain brand. I know I've had Shell, Sunoco, and Costco all mixed in.

I am curious to know as well. Anyone with any ideas?

[artieg30]

i'm running shell 91 octane here in Canada and can confirm i'm getting the same issue... not sure why the carbon splatters onto the bumper but it's definitely not noticeable in my EB II unless you look up at it very closely.

[ocso1606]

I run non-ethanol 92 octane only. the soot gets all over the back.