Reprogramming/resetting of ecu or transmission changes exhaust sound?

[topfuel]

Have previously changed aftermarket exhaust and it was really loud and alittle to a nuisance upon cold start. However after resetting or reprogramming of transmission by PML, the cold start sound and exos sounds changed to alittle more refined and different unlike before.

Even before the change of exhaust, on stock exhaust most beemers have that draggy cold start "zeengggggg" loud noise but I do not have that anymore with this exhaust.


Can any gurus explain the reason for this? Will this stay or revert back to the old sound like before? Or will the sound overall change once the ecu/transmission re-adapts again?

Thank u

 

[Red_Bean_Bun]

Re: Reprogramming/resetting of ecu or transmission changes exhaust sound?

You have an N55 engine ?

 

[topfuel]

Re: Reprogramming/resetting of ecu or transmission changes exhaust sound?

You have an N55 engine ?

Hi nope it's a n20

 

[topfuel]

Re: Reprogramming/resetting of ecu or transmission changes exhaust sound?

was told that the af ratio etc all would be reset to factory settings therefore is it better to reset/reprogram after a change of exhaust or nope?

 

[Red_Bean_Bun]

Re: Reprogramming/resetting of ecu or transmission changes exhaust sound?

High level adaptions can be reset. These adaptations are used primarily for minor acclimitization of the environment e.g weather or geographical conditions or fuelling in that location.

The Dme would make minor very limited adjustments but not major adjustments (that would be a tune) to the AFR for airflow or fuelling for an acceptable driving experience. Sometimes the injectors would be used for that purpose.

The ride is capable of adjusting by itself but if you are in a hurry .... Lhe mech can tell the ride to re-adapt on the fly.