Crackle and pop

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Morat
E30 Zone Team Member
E30 Zone Team Member
Posts: 8943
Joined: Thu Feb 09, 2006 11:00 pm
Location: The Peoples Republic of Yorkshire

Post Thu Oct 19, 2006 9:58 am

Does your 325 crackle and pop on overrun? Mine does when I'm coasting down from say 3k revs. It sounds great, but I'm starting to wonder if it means something bad is going on, cos I can't imagine its standard on FI engines!
The engine is stock, and the exhaust isn't anything special.

Please help with my paranoia!
E30 Touring 0.35 cD - more slippery than prison soap :)

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Turbo-Brown
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Posts: 4705
Joined: Tue Feb 15, 2005 11:00 pm
Location: Aldershot, Hants

Post Thu Oct 19, 2006 1:36 pm

Can be caused by a very lean mixture on light load whereby the fuel doesn't get ignited by the spark and builds up in the exhaust until something makes it go pop.

That or it's still burning when the exhaust valve open so it kinda pops out.

Shouldn't worry about it too much unless you're getting really big bangs?
325i Twin Turbo (until 10am 01/12/07 :( )

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