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Author Topic: Battery disconnect - now cars feels different?  (Read 1319 times)

Offline ttdan

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Battery disconnect - now cars feels different?
« on: December 09, 2012, 05:08:07 pm »
Hi there, disconnected the battery on my ED30 to leave it on a charger while I was away. The car seems to drive differently now, not really less power but the character of the delivery is definitely different.  Certainly has less of a whump when the turbo comes on boost but this could be that there was more lag before... This is a slight change, 5% max but noticeable. Anyway, cars is not (to the best of my knowledge) mapped so is t normal for the ECU to behave differently after a battery disconnect?

Offline sandancer

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Re: Battery disconnect - now cars feels different?
« Reply #1 on: December 09, 2012, 05:27:11 pm »
Sound like the car has just returned to default factory settings. Just drive it as normal and it will readjust itself to the fuel you use, driving style etc. Pretty normal really, it's happened to me as well in the past.

Offline Tfsi_Mike

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Re: Battery disconnect - now cars feels different?
« Reply #2 on: December 09, 2012, 05:50:37 pm »

If it was mapped, disconnecting the battery is known to reset the settings to stock.

Offline GrayMK5GTI

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Re: Battery disconnect - now cars feels different?
« Reply #3 on: December 09, 2012, 06:31:19 pm »

If it was mapped, disconnecting the battery is known to reset the settings to stock.

Only on Revo, Mike  :wink:
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Offline Tfsi_Mike

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Re: Battery disconnect - now cars feels different?
« Reply #4 on: December 09, 2012, 06:35:17 pm »

If it was mapped, disconnecting the battery is known to reset the settings to stock.

Only on Revo, Mike  :wink:

My Apr also goes into lockout mode

Offline GrayMK5GTI

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Re: Battery disconnect - now cars feels different?
« Reply #5 on: December 09, 2012, 06:36:14 pm »

If it was mapped, disconnecting the battery is known to reset the settings to stock.

Only on Revo, Mike  :wink:

My Apr also goes into lockout mode

Ah fair enough.

My R-tech doesn't  :wink:
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Offline ttdan

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Re: Battery disconnect - now cars feels different?
« Reply #6 on: December 09, 2012, 06:51:52 pm »
pretty sure the car is standard, have done nearly 30k miles in it now so pretty familiar with how it drives, it's the first time the battery's been off in that time so I suspect it's the ecu gone back to standard and will re learn, wonder how long that takes ?

Offline Polo6n1600i

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Re: Battery disconnect - now cars feels different?
« Reply #7 on: December 09, 2012, 09:28:51 pm »
We use to do this with older polo gt's to fool the ecu in going back to factory ecu setting. Them take if for a really good hard thrash. The ecu learned quickly and power delivery improved

Offline stealthwolf

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Re: Battery disconnect - now cars feels different?
« Reply #8 on: December 09, 2012, 10:01:29 pm »
+1. The ECU learns how you drive and adapts to it. I might have a boring week where I just commute slowly to/from work. You have to press the pedal hard to get it to respond/accelerate. If I then drive hard, stop the car, turn off the engine and restart it, I only need to dab the pedal before it launches ferociously.

The GTI isn't just a machine. It's very much a living, breathing thing.