cliffcoggin

I agree you need the car scanned by a decent code reader, however the battery warning light may be a clue. A substandard battery can cause all the symptoms you describe and a few more that you have not. I assume the battery was disconnected during your repair work. Did it lose charge during that time?

Stuart. While it is possible the water is rain coming in through the heater if its drain hole is blocked, or the heater matrix is leaking engine coolant into the cabin, or the windscreen sealant has perished, the obvious candidate has got to be the rag top. The fabric may be intact, but it must have some sort of seal around the edge which may have been damaged. I have never dealt with a soft roof so I can not be any more specific. You also said cleaning the drainage channels helped, so if they are accessible can you test each one by pouring a little water through them to see if they really are clear?

YES. Even on my 2007 car.

New batteries have to be coded to the car to get full functionality of all the electrical systems. Was that done?

Glad to hear the solution was so simple.

That's a good start. Do let us know if it solves the problem.

The possibilities are almost endless. ABS system, ECM, faulty gear selector switch, defective battery, wrong wheel/tyre sizes for example. You should get the car diagnosed by a decent code reader.

What do you mean by "changing gear strangely"?

Harry. Smoke like you describe is an MOT failure. Assuming you bought it from a dealer take it back for a refund or repair. On the other hand if you bought it privately be prepared for possible high expense, and tell us about mileage and service history.

In addition to Gareth's question, what size is the engine and how many miles has it done?

I have no idea what that means, but presumably you know how to enter the search terms of your choice into your preferred search engine. In other words the answers you seek are at your fingertips, and you need no particular expertise from this forum.

Yes, very suspicious. Possibly the rack sensor or its wiring was damaged during the wheel bearing change. It would not be the first time that repair of one fault created another by disturbance of the wiring. Apart from going to another company for a diagnosis, (without mentioning the problems with Vasstech or Kwikfit to avoid any prejudice), I don't know what to suggest.

Tony. The link leads to ten Duck Duck Go search results, only the first of which is a Youtube video, the rest being articles or web pages. If you don't like DDG use the search engine of your choice. P.S. I use DDG as my preferred search engine because I will not touch anything made by Microsoft, Google, Apple or any of the other spyware companies.

Definitely don't rely on Kwikfit for anything except tyres. They know little and care less. You need somebody that can properly diagnose the problem. Your best option for that is an independent VAG specialist.

https://duckduckgo.com/?q=A3+wiring+diagrams&ia=web

Yes that may be the problem. Having bought new parts why not fit them and prove the point?

I said the design was clever, I did not say it was good. Nevertheless it lasted 13 years which is considerably longer than many of the more essential components of a motor car.

I wouldn't call it a flawed design, in fact I'd say it is rather clever, however no machine lasts for ever. Yours has lasted 13 years so if you use rear screen wash normally through the new motor it will likely outlast the rest of the car.

Most likely the clutch needs to be renewed. How many miles since it was last done? Does the shudder happen as the clutch is slipped, or when it is fully engaged?

I'm with Steve on this. Get a new wiper motor.

Why travel all the way from Liverpool to London to buy a car? A3s are common so surely there must be something suitable closer to home.

I would either inspect it myself or get it professionally inspected. I would certainly not rely on MOT notes alone to make a buying decision. Bear in mind that the belt and pump will cost about £700.

You may well have damage to the wiring that connects the loom to the driver's door through a rubber bellows.

Thanks for letting us know Chay. Sometimes the simplest things get over-looked, and a perished hose has got to be the simplest weak point on the whole fuel system. It's something that did not occur to me.

I suggest the first place to check is the temperature sensor and its connections.