Back fire (popping noise) on deceleration

[nwills]

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I've noticed on my 650i Gran Coupe while in sport mode that when I come to a stop I get some "pops" coming from the exhaust...back firing. It's pretty much doing it 75% of the time.
It sometimes only gives me a gurgle with slight popping or an all out relatively loud pop!

Is this normal...anyone else experience this?

[neversummer78]

I got that too. I thought I ran over manhole cover a few times. I guess it is normal, since I am not the only one.

[SAMLAMBO]

Perfectly normal

[ctenidae]

Perfectly normal, and bad ass, when used correctly

I love that little backpressure burble.

[nwills]

Originally Posted by ctenidae

Perfectly normal, and bad ass, when used correctly

I love that little backpressure burble.

Used correctly!? Any tips you care to share!? :-)

[SAMLAMBO]

Originally Posted by nwills

Used correctly!? Any tips you care to share!? :-)

Put it into sports mode and use the paddles to downshift when you need to downshift

[coldfusion1998]

I have it too, love the sound although it scares my wife!

[ctenidae]

Originally Posted by nwills

Used correctly!? Any tips you care to share!? :-)

SAMLAMBO's downshift suggestion works if you have the automatic. I have a stick, so really, all I have to do is wrap it up a little bit and take my foot off the gas- usually goes "burble burble BLAP burble burble THUD burble burble"

Wrap it way up to red line and let off the gas, and you get the funky turbo whine as the wastegate opens, followed by the rumble and backfire.

I presume in an auto it's tougher, as you have to overide the transmission's clutch disconnect somehow.

[AC Schnitzer UK]

It's unburnt fuel from the engine burning in the exhaust. Perfectly normal. On some engines the fuel injectors are shut off completely on the overrun but this tends to make the ride jerkier. If you were permitted to run an open exhaust from the turbo onwards you'd see flames at night...