The manual specifically says "Do not disconnect the vehicle battery when the ignition is switched on or when engine is running. Otherwise, you will damage electronic components in the electrical system."

Well, I didn't mean to do it, but I did. I unknowingly removed the negative battery terminal on my 2001 A4 1.8T Quattro while the key ignition was in the ON position. I then subsequently hooked it back up in this same state. Since then, I have had terrible performance. When starting the car cold, it misfires here and there. Even when warmed up, it has about 1/2 the power it used to. Strange thing is that when I floor it, it sputters during acceleration until I let up on the gas, and as I let up, it boosts for about 1/2 a second like it should when it is running properly.

It is funny that the manual says "you will damage electronic components" instead of "you may damage". Ha ha. Well, it looks like they knew it was gonna happen. So, I guess my question is... now what? Where do I begin troubleshooting this issue? When they say "electronic components in the electrical system", I wonder which components they are referring to.

Ouch. Any help from the audi masters would be greatly appreciated.

 

i say take it to your local dealer or trusted shop

it might be something simple

 

yeah sometimes things that seem really serious arent so bad. but this isnt something you will just miraculously figure it out, you definately need to get the car checked.

btw, how did you manage to accidently do that? didnt know it was in the ON position i assume?

 

Throttle body alignment maybe?

Take it to get it scanned.

 

reset your throtle body

 

you need to run a few drive cycles for the computer to re-learn the settings.

http://www.findarticles.com/p/articl...4/ai_n11829961

 

chances are you cleared the system like a reset so you need to do a few drive cycles that's all

 

Thanks for all of your input. I will try the drive cycle idea (although I am not getting any lights) and have ordered a VAG-COM so I can reset the throttle body (I hope this is what I need). As far as the question of "how did I do that on accident" its just a matter of not paying close enough attention. I guess when I turned off the car, I had a reason why I turned it back on..like I was going to start it back up again and changed my mind at the last moment. Not sure exactly. Then I just forgot about it when I got out. I think there was a phone call mixed in there somewhere too. Basically, I am stupid.

 

You can attempt to reset the throttle body by turning the key to the position just before starting. Let the car sit for 3 or 4 minutes without touching the gas. It should align itself that way.

 

Jest, you should disconnect the battery for a few minutes, and then reconnect it before resetting the throttle body.