Corolla 141 2008 idle problem after replacing battery

[Sirimanna]

Hi Friends, My car battery dead and my father removed it and went to shop with old battery and bought new one and replace it. But now My car RPM totally wrong, And idea why is that? I google it and some said it will fine after couple of days.. but i really trust this forum, Pleas help me friends, Thank you

 

[tiv]

It’s relearning the idle sequence, drive it normally, will come back to normal

[Sirimanna]

  On 3/16/2020 at 1:18 PM, tiv said:

It’s relearning the idle sequence, drive it normally, will come back to normal

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Thank you Bro ?

[Rumesh88]

He should not have disconnected the old battery without a  back up. No that it is done drive for few more days to see if the idle speed settles down to its previous value.

[Sirimanna]

  On 3/16/2020 at 2:22 PM, Rumesh88 said:

He should not have disconnected the old battery without a  back up. No that it is done drive for few more days to see if the idle speed settles down to its previous value.

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hmm.. yes, hopefully it will fine, Tomorrow i  will drive on highway to galle, i will check and update.. thank you

[Sir Lancerlot]

  On 3/16/2020 at 2:22 PM, Rumesh88 said:

He should not have disconnected the old battery without a  back up. No that it is done drive for few more days to see if the idle speed settles down to its previous value.

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I thought only hybrids need a backup when replacing the 12V battery

[Davy]

  On 3/16/2020 at 3:28 PM, Sir Lancerlot said:

I thought only hybrids need a backup when replacing the 12V battery

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Disconnecting the battery on a car with an EFI engine causes the ECU to be reset. This throws the fuel trims and stuff which contributes to the rough idle. The ECU takes a while to re-learn and let the engine run smoothly.

If the car has a factory fitted navigation unit, the map data might be cached in the unit's memory which is volatile. If this is the case, disconnecting the battery without a backup erases the memory which will cause the unit to show the "Insert Correct Map Disc" error. 

Other obvious things that get wiped are your fuel consumption stats, mileages, radio stations, and other settings depending on options in the car. 

So no, it's not just hybrids. 

[Sirimanna]

  On 3/16/2020 at 10:03 PM, Davy said:

Disconnecting the battery on a car with an EFI engine causes the ECU to be reset. This throws the fuel trims and stuff which contributes to the rough idle. The ECU takes a while to re-learn and let the engine run smoothly.

If the car has a factory fitted navigation unit, the map data might be cached in the unit's memory which is volatile. If this is the case, disconnecting the battery without a backup erases the memory which will cause the unit to show the "Insert Correct Map Disc" error. 

Other obvious things that get wiped are your fuel consumption stats, mileages, radio stations, and other settings depending on options in the car. 

So no, it's not just hybrids. 

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Thank you Friend ?

[Sir Lancerlot]

  On 3/16/2020 at 10:03 PM, Davy said:

Disconnecting the battery on a car with an EFI engine causes the ECU to be reset. This throws the fuel trims and stuff which contributes to the rough idle. The ECU takes a while to re-learn and let the engine run smoothly.

So no, it's not just hybrids. 

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Yeah that makes sense, but I've never noticed anything different when I changed the battery w/o a backup on my Lancer or the previous Belta 

[Twin Turbo]

  On 3/16/2020 at 1:07 PM, Sirimanna said:

Hi Friends, My car battery dead and my father removed it and went to shop with old battery and bought new one and replace it. But now My car RPM totally wrong, And idea why is that? I google it and some said it will fine after couple of days.. but i really trust this forum, Pleas help me friends, Thank you

 

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When did you last replace the air filter? if you can't remember, just get a new one,.get a full tank of regular go juice,

It's call'd an adaptation run, just normally drive the car up to a highway and nail it,..

 

TT.

 

[Sirimanna]

  On 3/17/2020 at 9:18 PM, Twin Turbo said:

When did you last replace the air filter? if you can't remember, just get a new one,.get a full tank of regular go juice,

It's call'd an adaptation run, just normally drive the car up to a highway and nail it,..

 

TT.

 

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Thank you soo much i will do it