Not joined yet? Register for free and enjoy features such as alerts, private messaging and viewing latest posts and topics.

Cold Start..

Specific discussion about the E89 2009 Z4 (sDrive35is, sDrive35i, sDrive30i, sDrive23i)
Post Reply
User avatar
Burple
Member
Member
Posts: 58
Joined: Tue Jul 11, 2017 12:01 pm

Cold Start..

Post by Burple » Wed Jul 26, 2017 12:26 pm

Hi all,

I've had a quick search on the forum, and a wider trawl of google and I *think* I know the answer to my question, but can anyone on here give a definitive answer?

Is it a "feature" of the e89 (18i - or in fact any of the 2.0 turbo direct injection engines) sound rough as a bag of badgers @rses for a bit after a cold start?
google says pretty much yes, but I thought the proper experts could probably settle it.

when I say rough, I mean kind of like a blowing exhaust. give it a blip of throttle, noise goes, then resumes when back at idle.. last for a bout 20 - 30 secs after cold start up.

Cheers!

User avatar
Smartbear
Lifer
Lifer
Posts: 13685
Joined: Wed Feb 05, 2014 6:54 pm
Location: a barn in Somerset

Cold Start..

Post by Smartbear » Wed Jul 26, 2017 12:28 pm

Burple wrote: Wed Jul 26, 2017 12:26 pm Hi all,

I've had a quick search on the forum, and a wider trawl of google and I *think* I know the answer to my question, but can anyone on here give a definitive answer?

Is it a "feature" of the e89 (18i - or in fact any of the 2.0 turbo direct injection engines) sound rough as a bag of badgers @rses for a bit after a cold start?
google says pretty much yes, but I thought the proper experts could probably settle it.

when I say rough, I mean kind of like a blowing exhaust. give it a blip of throttle, noise goes, then resumes when back at idle.. last for a bout 20 - 30 secs after cold start up.

Cheers!
Yep, they do that-I think it's the air pump keeping the emissions low on cold start?
Rob
Image

e89 Sdrive 20i, plenty of mumbo & good economy-the thinking bears z4
e89 Sdrive 30i, this ones busted, pass me another...
e85 3.0si sold

User avatar
Burple
Member
Member
Posts: 58
Joined: Tue Jul 11, 2017 12:01 pm

Cold Start..

Post by Burple » Wed Jul 26, 2017 2:44 pm

Cool, that's what I figured... Thanks! 8) 8)

Image

(sorry.. it was that or Clive Dunn!) :rofl:

User avatar
R.E92
Senior Member
Senior Member
Posts: 1644
Joined: Wed Dec 04, 2013 10:10 am

Cold Start..

Post by R.E92 » Wed Jul 26, 2017 3:16 pm

On cold start the car alters the VANOS positions which changes valve timing to heat up the cats quicker. You can disable this in the DME.

VANOS position alters the tone of the exhaust quite significantly. Duration is usually between 45 and 60 seconds.

User avatar
Burple
Member
Member
Posts: 58
Joined: Tue Jul 11, 2017 12:01 pm

Cold Start..

Post by Burple » Wed Jul 26, 2017 4:24 pm

Excellent, that's pretty much what I'd read, perfect explanation thanks! 8) :thumbsup:

KYT1107
Newbie
Newbie
Posts: 1
Joined: Sun Aug 13, 2017 2:36 pm

Cold Start..

Post by KYT1107 » Sun Aug 13, 2017 2:56 pm

Found this topic really useful thank you :)
I've just bought my first Z4 and never noticed this noise the two times I test drove the car, but the first time started at home sounded awful and had visions of needing a new exhaust straight away!!!

Post Reply