cliffcoggin

How did you check the battery? A simple voltage test will tell you nothing about the real condition of the battery. It needs a deep discharge test, (i.e. a load of more than 200 amps rather than the few milliamps of a multimeter,) to simulate real conditions and reveal internal faults. If your battery is original there is a fair chance it is defective and responsible for the faults you noted.

Wire breakage is common within that rubber bellows, usually on the driver's door as that gets the most use. Search the forum for other instances. Be glad it is only the speaker affected, it's often the door lock or the window.

Would that be the same Audi centre that told you a new diff was needed? Why take their word for it when it is so easy to check for yourself.

No, I don't know the location of the terminals. If you can see the element it should point to them.

Assuming the sun roof was not hit by a stone or other missile, then there is no doubt that the dealer who sold you the car is liable for its repair. It may well be a manufacturing fault at Audi that led to its destruction, but it is the vendor who has liability. The dealer will undoubtedly prevaricate but don't give in to him. Demand either a replacement car or a full and guaranteed repair.

I think it's safe to say the differential is not the problem, and that the mechanics you consulted are guessing. I suggest you work methodically through the possible causes, eliminating each in turn, and hope to arrive at a definite or at least probable cause. Start with the tyres as mentioned by Magnet in 2022, then wheel bearings, rear tracking, CV or universal joints, prop shaft pillow bearing. The tyres are the most likely culprit. Look for mis-matched tread patterns, wrong pressure, and balance.

The points most susceptible to damage are the terminals where the supply connects to the heating element. Have a good look at them first. If possible, test for power at those terminals with a volt meter. It would also be worth inspecting the wires that pass through a rubber bellows between body and boot lid. They have been known to break with the repeated flexing as the lid is opened.

A new differential is a drastic measure that is rarely needed. What other possible faults did you eliminate before then?

Was that a professional diagnosis or one you did yourself with a cheap code reader?

So what do you intend to do about it? In your position I would write a letter or email of complaint explaining the fault and demanding it be repaired. Do not use phone calls or text messages for that purpose. You need evidence that can be produced in court should it ever get to that stage.

Ah, so better atomisation is the key. That makes sense and is something I should have thought of for myself. Thanks for the explanation.

Those of a kindly disposition might think your dealer is snowed under with too much work to attend to your minor faults. Those of a more cynical nature, such as me, might suspect him of prevaricating in the hope that you will give up until after the guarantee runs out.

Dion. There will be a drain for condensed water from the aircon casing, which is why there are often water drips on the ground when the car is parked after a drive in humid conditions. There is a good chance your drain line is blocked. I don't where it is or what form it takes, but you will need to find and unblock it.

Steve. I am struggling to understand how a high fuel pressure makes starting easier. Diesels rely on compression of the fuel/air mixture to raise the temperature high enough for auto ignition. I understand glow plugs can supply extra heat in low temperature conditions but how does fuel pressure at the injectors come into it?

Josh. Don't be surprised if you get very few replies. We are not ignoring you, however most members are British and have no knowledge of American parts suppliers and car breakers (aka recyclers).

Cars do not repair themselves, so be prepared for something similar to happen again.

It would if the locks are still vacuum operated and that pipe was still part of the vacuum circuit. However if you can easily pass air down the pipe without an effect on the locks then the pipe can be eliminated from further investigation.

Unless you have a high quality code reader I suggest you ignore it and get the car scanned professionally. Most cheap domestic code readers are so misleading as to be worthless. There are a few possible causes for your problem that include a defective battery, a faulty instrument panel, and a faulty ECU amongst others, but you will not know without testing.

The reduced heating is consistent with a blocked heater matrix. The garage report confirmed no flow, and though the garage tried to flush it, there has been little success. I'd say you need a new heater matrix.

Another thought. You mentioned an open ended pipe in the boot. Does blowing or sucking on it produce any response at the locks? That should tell you if it is connected to anything.

If diesel, Adblue, ULEZ etc. are a concern for you, have you considered a battery car? As long as you have off road parking at your house for cheap charging the higher purchase cost will soon be offset by lower fuel costs and zero road tax.

What an intriguing puzzle. In my experience vacuum pumps are rarely silent so I would expect you to be able to hear it, even if the noise is no help in locating it. If you can not hear it I wonder if the car has been converted to electric locking.

Ah. I wrongly assumed it was metal.

I can't help with a source, but if the current flange is cracked or warped it can probably be repaired by a local small engineering company.

The fault may not be the connector. I suggest you follow the wires from the white connector looking for cuts, abrasions, poor connection at the other end, etc. before buying new parts.