Hi,

Sorry for the long post, but I want to describe my problem in detail.

Today my 99.5 A4 2.8QTip developed a problem with its transmission. It has 89k miles. Originally I had some kind of problem with the battery or the electrical system, which I was trying to fix. It would go dead after sitting for about 6+ hours and I wouldn't be able to start it. I was testing the battery and everything seemed ok, although I know something is definitely wrong . I assume there's some kind of drain on the battery I'll need to hunt down but this isn't the main reason for my post.

I wasn't able to fix the problem but I seem to have developed an even bigger one! Here's what I did and what happened...

We have a small family owned shop that I've been working at for a couple years so I have some automotive knowledge, mostly in front-ends, brakes, and tires. I've been having a problem with my audi, so today I tested the battery with an electrical test kit. First, I disconnected the wiring from the posts and attached a charger. I ran the charger at 12 volts-60amps for 3-4 mins. I tested the battery and it read the correct voltage. So with that not being the problem, I reconnected the battery. I decided to disconnect the power wire from the back of my sub woofer thinking it might be draining the battery somehow. I put electrical tape around the end of it and set it aside. That's all I did and decided I would continue tomorrow...

As I leave and pull out onto the road and begin to accelerate to around 20-25mph, the rpms shoot way up from about 2500 to at least 4500 (I'm pretty sure it was 2nd to 3rd but I'm not 100% sure. It may have been 1st to 2nd.) There was about a 1 second delay where the engine revved freely as if I had it in neutral and then the tranny engaged with a horrible thud. I pulled over into a lot. No CEL, no limp mode, no lights of any kind.

I shut it off, waited a few minutes, and tried it again. The problem was still there as it was before. However, if I let off the gas quickly when the rpms shoot up I can keep the tranny from engaging. This is the first time I've had a problem with this car since I bought it besides an oil leak from the valve covers which was fixed in March.

I drove it around a bit and noticed that when I accelerate very slowly it will shift itself through the gears, although not like it normally does. The shifts are very close together and it hovers around 2k rpms. In tip mode I am able to shift it like usual and it seems ok, mabye a little rough(but that could be my mind playing tricks on me) I didn't take it on the highway to see what would happen with 5th or higher speeds.

Where should I start tomorrow besides looking at the area around the battery where I was working? I have less than a mile to drive so I figure it'll be ok to drive it there. I don't have a VAG-COM but I do have a professional scanner called an OTC Genysis being shipped to me later this week. Hopefully I can do something with that if I know what to look at.

I'm thinking it has something to do with me disconnecting the battery because it would be a hell of a coincidence if it didn't. Is there any possiblity it has something to do with my battery going dead? Mabye a malfunctioning electronic part/sensor? I searched and couldn't find an answer to a problem like this in the forums. I'd really appreciate the info anyone who knows these cars can give me. Has anyone had this problem and fixed it? Thanks.

 

If you are DBW, you need to do a throttle body alignment.

 

I appears to not be DBW. I can see what looks like the wound cable for the throttle buried under some wiring and hoses in the back of the engine behind the intake. It runs up and through the firewall. Hard to get a good look at it though without removing stuff.

I tried a couple methods I read on Audiworld for reseting it anyway, and it didn't help. 1st I turned the key to on, pressed the gas all the way down for 5 seconds, shut it off, depressed the gas, waited 3 minutes, no go. Then I just left the key in the on position for 3 mins, turned it off for 2, also no luck.

I spoke to a guy that was over here today. I don't know if he's a reliable source, but he told me he had the same problem in a lincoln and it was the transmission bands slipping. I find it hard to believe that it would be a coincidence like that though. It must have something to do with me messing around with the battery. Any other ideas?

 

For future reference if anyone comes accross the same problem...

I fixed it by doing a throttle body reset with vag-com. Thanks CrazyHawk for leading me down the right path.

 

Good to see you fixed it, but the correct way to set the throttle body without the VAG COM is to leave the key in the on position for 10 minutes not 3.
Good luck with the OTC scanner, i hear its a good one.