Ok I am building a stereo system in my car and today I added a new xs power battery. Now my car is not shifting right. Seems to me that it is hesitating to shift and maybe slipping some. Can a battery really cause these issues?

Disconnect the xs power battery and if the problem goes away you know it's the battery you added.

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I talked to my grandpa and he tole me that they use a plug that goes into the obd2 port to keep juice to the computer while the battery is changed out. He said since I didnt do this that could be the problem. I really dont know. I dont see how it could be the battery because I saw a guy over the weekend with a bigger battery than what I have and also xs and he has no issues. I was told the car may have to relearn its self

-- Mon May 02, 2011 8:53 pm --

Also I didnt add a second battery, I added a better than stock battery.

every time i disonnect my battery it does take the pcm a little bit to shift well again. It shift's really soft and mushy for a while so that may be your issue

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Comp G: 3.2-E85-65's-headers-rockers-104's-DHP tune & "other stuff that doesn't matter"

Yeah mine does the same thing and I was told that it does this because it has to re-learn the drivers driving habits. So I decided to start hooking up a battery to a cigarette lighter plug in so the ecm will have power while I switch shit in and out

Out of the thousands of times I've turned off my battery, or the one time I switched it out, I've never had this issue.

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2004 Grand Prix GT2: cone air intake, rebuilt HD transmission, rebuilt camshaft, rebuilt top, repainted black rims, rebuilt suspension, slotted/cross drilled rotors, Pioneer AVIC-D3 TV stereo, and more!

if the battery is disconnected for more than 20 minutes, the PCM resets itself and it has to go through the relearn pattern once again, for about the next 200-300 miles, the trans will feel like it is sleeping because the PCM has to relearn the shifting points at certain RPM's...someone feel free to correct me if I am wrong...I'm not a tuning person by any means, but that is just what I have heard.

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From experience, I will have to agree with you. I had my battery unplugged for a full day, and right when i went back to test it out, It went to wicked high RPM's in every gear. It accelerated a hell of a lot faster than before it reset though...

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