Resetting the ECU

[Yanahdi]

Hi all,
I just recently remembered to reset my ECU by disconnecting my battery after I've had my new exhaust on for about 5 months. (Doh!) I neglected to do this after I got my Apex'i WS exhaust. After re-connecting the battery I noticed a marked difference in the sound of the exhaust.

Is this normal or just psychological?
The only thing that the exhaust changed was the pipes after the cat, would this really change the flow characteristics enough to warrant a change in exhaust tone?

[brink]

Well, initially it'll change the way the engine runs as it relearns how to run your engine again. After that, when it's learned how to run with the new exhaust, it sees different combustion behavior with the freer flow, so it's gonna provide different a/f ratios and thus change the way the engine sounds.

[Yanahdi]

hmm. I never would have thought that the marginal amount of free flow from the exhaust would change anything until I did F/I.


Thanks for the reply, thats a load off my mind.

[eecc]

take ne pics of the exhaust?

[Yanahdi]

nah I don't have any pics of it. Are you thinking of getting the Apex'i ?

[eecc]

yeah, its exactly what i want: performance gain w/o sacrificing my ears. i jus wana see how it looks on the car first.

[Night Speed]

Originally Posted by brink

Well, initially it'll change the way the engine runs as it relearns how to run your engine again. After that, when it's learned how to run with the new exhaust, it sees different combustion behavior with the freer flow, so it's gonna provide different a/f ratios and thus change the way the engine sounds.

hi
i just reset my ECU by disconnecting my battery and after 15 mins later i connect the wire back and turn on my engine. i noticed that my engine shakes really hard and make a weird noise, too. but after 2 mins later it stop shakeing. so is that normal?
thanks

[CamNub]

Way to bring back an old thread.

Does it still shake, or only when you reset the ecu?

[Night Speed]

Originally Posted by CamNub

Way to bring back an old thread.

Does it still shake, or only when you reset the ecu?

now seem like didn't shake. only that time when i reset my ECU

[Toysrme]

Just re-learning the fuel trims & more than likely was having to adjust the ignition timing at the same time.