Erin Wisbey

I have a used 2001 A6 Quattro that had slight front end damage, mostly cosmetic.

Several things have happened all at once so I'm not sure where to start. I had recently noticed drastic wear on the inside of my driver front tire. I took it in to a shop and they said I needed tie rod ends, struts and bushings. There is only one shop in my area that will work on Audis and they are always busy. Last time I took the car in, it was three weeks to even diagnose and another 2 weeks to begin labor and they do not do rentals.

So I just bought some used tires to get me around till they could fit me in. I don't have any other symptoms of alignment/front end issues except a slight vibration above 70mph.

Next issue, the ABS and traction control lights came on while driving to work. I pulled over, turned the car off then started the car and the lights did not come on again. When I got to work I noticed a burning brake/oil/plastic smell and I thought I saw a tiny bit of smoke from under the front of the car. On the return trip, no lights no smell.

A couple days later and the lights come on and go off again. Then it happens frequently, sometimes with the smell sometimes not. Sometimes the light comes on while going over train tracks or bumpy roads. Sometimes the lights stay on all day even after restarting. Then I noticed a feeling like there was a stuck brake, a sluggish slowed feeling like the car was being held back, but it was random and didn't last long, so I thought maybe I imagined it.

This last week I drove just over 100 miles on the freeway through heavy downpours and lots of standing water. The car drove fine and had no issues, no dash lights. When I reached my destination I parked my car with the passenger side tires in the gutter next to the sidewalk, which tilted my car only slightly towards the passenger side. I left my car parked for four days, and it rained heavy nonstop the entire time.

When I got in to return home I noticed the entire passenger side floorboard was filled with standing water all the way to the door seal. All my windows and sunroof seemed to be sealed tight and I could not find the source of entry for the water. I bailed the water out and towel dried the car, then got in to leave. When i turned the car on the ABS and traction control lights were on. As I pulled away the car felt very sluggish and I noticed the rpms were a lot higher than normal for the speed I was going. I pulled into a parking lot and restarted the car but the lights stayed on and I could smell the burning smell more than normal.

I slowly drove around the lot putting the car in park, reverse, restarting it and even putting it in crossover mode in 1st and 2nd but nothing made the dragging feeling go away.

The burning smell got worse and felt even more sluggish like I was dragging the back tires. I left the parking lot to return to the house I left, and the car slowed so bad I was afraid to continue driving it. I had it towed to a garage to dry out before checking it further.

I will be checking it this weekend but need help on where to even start. Do some of these things seem connected? Is the water damage even a factor? What should I start on first? Any thoughts are appreciated!

MP4.2+6.0

Quite the project. In terms of value, honestly car may be totaled.

I owned a 2000 A6 4.2, so perhaps know the issues.

1. Tire wear is likely upper control arms in front suspension. The inner bushings more specifically. Standard A6 wear point, at least on 4.2, and that characteristic tire wear. It throws alignment off during braking, but may not see it with a static alignment check. Might relate to freeway speed slight vibration you feel too--besides the obvious wheel balance questions of course.

2. Water. Likely the plenum cover is dislodged under the hood, particularly at U.S. passenger side right at lower windshield corner. Water comes in through HVAC air filter you can see with the cover removed and heads down through heater unit and out the vent under the front seat. Transmission computer is under the carpet toward front, so it is critical you get it all dried out. I would not drive it or start it until you have it dry, most critically around that unit. That damage alone can total a car of this age and value. Get the plenum cover correctly seated, and if it is missing or broken, a critical part. Also check that plenum is draining, and clean out the area in general of plant and other debris. From lack of power description, maybe tranny is in SAFE mode? If gear shift display is reversed as far as the lighting, that has happened. Not good outlook for tranny computer at that point, though you can try drying and then clearing codes with VCDS or similar tool shop may have.

3. Brakes--expect one brake caliper may be hanging up. For me it was the passenger side rear. I first noticed at a gas station from the burning brakes smell and found that one rotor really hot and pads badly worn on just that one even though recently replaced. I bought a junkyard brake caliper and just swapped it out.