ok i know it sounds weird..maybe im imagining it but after i recet my ecu (overnight battery terminal removal)..the stock exhaust sounds a little different...doesnt sound as throaty and doesnt sound the same in the higher revs...anyone know what it could be?...my sig isnt updated..i put the stock ex back on and i have everything else..its kinda weird

 

You're not imagining it. After a reset, the ECU uses a preset air/fuel and ignition map. These maps lean on the conservative side which the A/Fs are rich and the ignition is dialed back a bit until the ECU learns over the period of about 30 to 40 runs. You will probably notice worse MPGs and reduced performance in the short term along with boggy tip-in throttle performance and reduced induction noise.

 

^^^^ what he said

 

so it will go back to the way it ways after some time right?..i always thought reseting the ecu was good for performance reasons...like it runs as if the car already had the boltons...

 

bump..just wanna make sure it will return back to the way it originally was..

 

What DaveB said is correct. The ecu will set itself back up again. Its a quite common misconception that reseting the ecu somehow gives you more performance or that your car can get into "granny mode" if you drive it slowly. The only time a ecu reset might be helpful is if you just added a mod that changes your a/f ratio. In this case, the car will def learn to set itself correctly, but reseting the ecu might help it do it a little quicker.

Theres really no reason for you to ever reset your ecu if you haven't done anything to your car and theres nothing wrong with it. Nothing to worry about though.

 

wouldnt putting my stock exhaust back on change my af ratio?...