Hi. I’m new here and don’t know much about the engines on cars. Any issues I normally take it to my local Kwick fit. But have moved and don’t trust what’s happening So have a question to ask. I have Audi a4 2lt turbo s line. 07. About six months ago my engine light came on. Took it to a different Kwick fit and they say I needed a lambda sensor. Changed it. Then said that the light came on again and that I have air in the system and basically take it somewhere else as they can’t fix it. So if I went. The light came back on. Someone I know had a computer so plugged it in. Code was p0171. System to lean. Bank 1. So away I went. Light came back on. Went to a garage. Reset it. Light came back on. Went back to garage Explained it all and they said I needed a new air breather. So had that done. Went away. Light came back on. Went back. The checked it. Said that I have air in the system and they don’t have the equipment to find out why. So went away. Found a friend of a colleague that has his own business. Basically ended up changing the other lambda sensor. Went away. Light came back on. All the time the light was off and on. There was no issues with driving the car. It accelerated brilliantly. I was always driving for two hours on motorways. No problem. So I drove from sandbach to Grantham. Then to cov. Stopped in cov. Started the car and it sounded like I had blown my exhaust. When I got back to sandbach. Went to a garage. Explained all of this. They said they can do a smoke test. It found no leaks. So they did a compression test. Found cylinder 2 is on 140psi. While the rest are on 180psi. They say indicating a cylinder leak. And need a new engine. But when I picked it up. It was a completly different car. Badly shaking and no power. It wouldn’t go above 30. Rang the garage and they said it’s because of the misfire. I don’t know what to do. Someone said about the spark plugs. So got them changed. Nothing. The guy that came out to do them from a garage. Maybe try the coil pack and I can do that myself. Should I just scrap it. Or is there something else I can try. Really, really love that car. Spent a fortune on repairs. I’ve had it 5 yrs and it’s just coming up to 200,000 miles. Help please