N55 exhaust sound at startup

[hurrican3]

The N55 comes with a "butterfly" exhaust for what I've heard. Upon cold startup the exhaust flows only though the right side and is much louder than after about 30s of idling.

Can anyone explain why this is so?

 

[Jason8822]

Re: N55 exhaust sound at startup

Not all N55 equipped engine have.

 

[Cateye]

Re: N55 exhaust sound at startup

Left valve is close so as to speed up the warmup process..

 

[hurrican3]

Re: N55 exhaust sound at startup

Left valve is close so as to speed up the warmup process..

Wow that's really advanced! Thanks for the brief and precise explanation!

 

[egg2]

Re: N55 exhaust sound at startup

Unplug elec connector to get a slightly more audible "purposeful" drone from 1500-2000 rpm when cruising.

 

[Red_Bean_Bun]

Re: N55 exhaust sound at startup

Unplug the connector will create a fault (will not show on dash). Prefer to unplug the vacuum tube and stuff a screw at the tip......

 

[hurrican3]

Re: N55 exhaust sound at startup

Where is this vacuum tube found?

 

[Jason8822]

Re: N55 exhaust sound at startup

Where is this vacuum tube found?

Its a rubber tube beside the valve, some valve before the muffler, some valve after the muffler

 

[Codewerx]

Re: N55 exhaust sound at startup

Yup ..... It leads to a valve along the tailpipe .....

 

[MTechnic]

Re: N55 exhaust sound at startup

Bro- our cars have this?

Unplug the connector will create a fault (will not show on dash). Prefer to unplug the vacuum tube and stuff a screw at the tip......

 

[Red_Bean_Bun]

Re: N55 exhaust sound at startup

If the muffler is stock - Yes.

Bro- our cars have this?

 

[MTechnic]

Re: N55 exhaust sound at startup

Cheers bro

If the muffler is stock - Yes.

 

[hurrican3]

Re: N55 exhaust sound at startup

Does the valve open up only at higher RPM or does it automatically open when in sports mode?

 

[Red_Bean_Bun]

Re: N55 exhaust sound at startup

Opens at 3500 rpm ...

Does the valve open up only at higher RPM or does it automatically open when in sports mode?

 

[hurrican3]

Re: N55 exhaust sound at startup

Opens at 3500 rpm ...

You da man!!

 

[hurrican3]

Re: N55 exhaust sound at startup

Checked the flap on the left exhaust this morning and found it to be open. So at cold start how does the sound only come from the left? Unless I have been looking at something else.

 

[Red_Bean_Bun]

Re: N55 exhaust sound at startup

Cold start one side closed for warm up ........

Checked the flap on the left exhaust this morning and found it to be open. So at cold start how does the sound only come from the left? Unless I have been looking at something else.

 

[hurrican3]

Re: N55 exhaust sound at startup

But before I started my car this morning I used my iPhone torch and saw that it was open.

 

[Red_Bean_Bun]

Re: N55 exhaust sound at startup

No vacuum bro ........

Need vaccum to close......

But before I started my car this morning I used my iPhone torch and saw that it was open.