I replaced the battery on my 2005 350Z automatic. Since the replacement the car does not have the same performance when driving hard. It seems like the shift points are not the same. The battery was removed for over a day and I heard the ECU and maybe TCM were reset from the battery removal and the transmission may be learning my driving style again.

Has anyone else experienced this? Is there a way to put the car back into a performance or aggressive mode? I assume I can drive hard and it will eventually adapt. Anyone know how long that may take? Or the best way to tell the car, 'hey, lets go!'

 

That's very odd, I've never heard of the performance suffering after a battery replacement. But my experience after leaving my battery out over the winter is that I failed emissions because I guess the car's computer wasn't talking with the computer at the emissions place and also my car would shut off if I never kept the revs up after I started it if it was warmed up already. It took about 100 miles of driving before things went back to normal. But I never noticed any significant drop in performance though. Then again, I have and 03 manual and you have a rev up auto so things might be different.

 

I would drive it more and see if it re-learns. As long as there aren't any CELs, you should be fine... are you stock or was it tuned?

 

No CEL's and I have the stock ECU. I have been testing and when using triptronic I can keep it in gear longer and it's quick... but it used to behave like this in full auto. I tried calling Nissan to figure out how long the adaptive/learning process can take and they said there is no estimate for the process. I'll keep driving and see how quickly it can learn.

 

when I unplugged my battery for my steering wheel install my 03 ran like **** for a couple days after. up to a week later it would still stall at idle. it has completely cleared up now but I notice that every time my battery is unplugged for more than 15 min or so the ECU has to start all over.

 

That's weird I never have any problems when mine is left unplugged.

 

The synchronized inhibitor modulator has been detuned. It requires a 3VDC trigger to reactivate and relearn, to initiate the shift servo in the transmission. The dealership should be able to help putting this back in aggressive mode...

 

vo7848, do you actually know what you're talking about or would you also recommend I replace the flux capacitor? lol sorry just never heard of what you just mentioned.

 

I'd recommend looking at the twin-flux capacitors, going for a quad setup may be pushing it.

With all seriousness, it's probably your ECU relearning, give it a week or so and see how it responds after. If you still don't like how it shifts:

1) TransGo Valve Body Upgrade (would recommend pairing this with a transmission cooler, and say hello to chirping shifts)

2) Ask your UpRev tuner to play around with line pressure

 

Maybe you didn't put the battery back in correctly.

 

If it's starting I'm pretty sure it's in right.

 

It'll re-learn. Did you get a new battery with the required amperage? Or a lesser battery?
Maybe you can try the accelerator pedal re-learn process once.

 

I was just pulling your leg...