cliffcoggin

Glad to read the problem was non existant. However I believe you still need to code the new battery to the car despite maintaining 12 volts during the swap.

Very true, but best done out of the tourist season.

My guess, and it is only a guess, is that VCDS will not accept the code for your new battery because it is the wrong capacity. Why have you fitted a 70 Ah battery when Audi wants 92 Ah?

So are you talking about third party cards ready loaded with maps etc? If so, be wary. The reputation of such suppliers varies a lot. Some good, some bad. I first assumed you were trying to copy the navigation system from a source to a card.

I doubt it is an electrical or sensor fault because the electrical system is off when the car sags. It is more likely to be an air leak from the bag, valves, or pipe. I would spray or brush soapy water on all the components and watch for bubbles.

I wasn't aware you could get Audi's navigation system from anybody but Audi. Or do you have something else in mind?

Where?

Thanks for that.

Mansour. Have you come to a decision on this? Were the responses of any help?

I suspect the drop soon after starting is when the thermostat opens and allows cold water to reach the temperature sensor. Perhaps other owners can confirm if this behaviour is normal.

Count yourself lucky it is only a noisy pedal. Audi are selling hybrid cars which irretrievably break down after a year or two. Audi is no longer the highly reputed company it once was.

I don't believe it, but if the test was done by Halfords I am not surprised. Were you supplied with a report of the voltage drop during the test, or an indication of the remaining capacity?

Thanks for putting the recording as an attachment in today's message; I refuse to download anything from untrusted sources. The noise sounds very abnormal, though I have no idea what it could be. Is the braking normal when in motion, with no odd noises or pulling to one side?

Is that new behaviour or has it always been like that? Does the guage stay at the normal reading on long journeys once it has risen for the second time?

Unfortunately Ted, none of the earlier respondants in this topic have bothered to return to the forum with either an explanation or a solution, so we are as much in the dark as you. As mentioned earlier, report it in writing to Audi on the slight chance that the company might one day look into it.

I am puzzled how Audi can tell you there is a leak if there is no visible sign of oil outside the engine. Have you been under the car to inspect the underside Jamie?

Sorry if I was unclear. If the instrument panel or cluster is faulty, which you can only discover by having it tested, it must be repaired or replaced.

A3s of that era were prone to failure of the instrument cluster which gave similar symptoms to your car, so it is possible your A6 suffers in the same way. Audi will want a small fortune for a new cluster in England or a large fortune in Norway. The clusters can be repaired at much lower cost if you can find a suitable company. If you can not find a local company it would be worth investigating if ECU Testing, a company we often recommend here, would do it.

That means you have a defective battery. In normal circumstances you should treat an AGM battery the same as any other type of battery. City traffic is exactly when the stop/start function is designed to be used. If your battery can not support that sort of use then it is defective.

Keiron. I can't tell you how to attach a file from your phone; I can tell you that even if you manage to do so it is unlikely to demonstrate the noise you are asking about. Many people have tried over the years and invariably all we can hear is normal engine or road noise. If you want to try again you will need to put the microphone close to the noise source so that is is not drowned out by all the other sounds of a car.

Aaron. Have the above responses been of any use to you?

James. Have the above responses been of any use to you?

Jump starting from an external battery or a booster pack does not count as a stable power supply, particularly when you consider their flimsy cables and lousy contacts at the crocodile clips.

Cars from twenty years and more ago had a lot of tolerance for feeble power supplies; modern cars do not. Their electronics require very stable power in order to work properly. Don't forget to get the new battery coded.

You have done this sort of thing before so I daresay you know about the legal requirements in some countries to have a first aid kit and reflective red warning triangle in case of breakdown. Are headlight beam deflectors even available still? Years ago I would have fitted LHD bolbs for foreign travel, but I imagine that could be rather expensive nowadays.