Hey guys I'm new to Audi's and need some help. I bought a 2005 Audi S4 B7 with 101,000 miles about a month ago. The car drives great and really comfortable ride. Car looks like new from the outside and inside. The problem is about a week ago I went through a muddy area about 15-20 feet long. I went through it slowly and when almost touching pavement the ESP light and EPC light came on the same time. Once that happened I immediately parked the car for about 3 hours. I turned it on and the CEL was on including the other previous lights and at idle the car was shaking and the CEL starting blinking. When I put it into drive it stopped shaking and seemed to drive fine but I noticed that the rpm needle wasn't moving consistently. It moved as if I was accelerating and letting it off every second. It didn't feel right either the acceleration felt jittery. When I got to my destination I unplugged my battery for about 10 minutes and plugged it back in. All of the lights disappeared for about two days, but the CEL came back on while I was stuck in traffic and started shaking the car. But since I was in traffic I wasn't going to turn off my car and once I sped up more than 10 mph it stopped shacking but shortly after the other lights came back on. And kept driving going about 70 mph when all of a sudden the car felt like it lost power and when I would press on the gas it did nothing and kept on slowing down when at about 30 mph the car shut off. I stopped on the side of the road and turned it off and on and tried to accelerate but it only accelerated slowly anf couldn't pass 20 mph. I turned it off an on about 4 times and took the lights off just enough to get home. My neighbor has a BMW and asked him for help. He has a code reader and told me that I have misfires on a couple cylinders and one of the codes that was different than the others was P0601 I think is what he said. He told me that I might need to switch my TPS sensor and for the P0601 code he said that I might need a new ECM. I don't know if you guys have come across any problems similar like this. Or if I do need a new ecu? And if I do could I buy a used one, and could I just connect it or do I have to take it to the dealer so they can program it. I'm located in Dallas and like I said I'm new to Euro cars, do y'all have any suggestions of any good shops in Dallas that I could take it to? The car is currently on limp mode and won't let me pass 20 mph unless I unplug the battery and plug it back in. I have stopped driving my car to prevent any damage. Any kind of help would be greatly appreciated. Thanks.