cliffcoggin

I thought you had changed the top mounts already, Andy.

Look at the top spring mounts. If the spring does not seat correctly it can lead to creaking. You will need spring clamps to restrain the spring in order to move it.

As far as I recall those can also be the symptoms of an instrument cluster fault or an ECU fault. I don't know how you would pin down the actual problem except by replacement, which of course is a hugely expensive solution that could easily exceed the value of the car.

I don't recognise the noise, but it's odd that the clatter rate seems to be constant even when the road speed increases.

https://duckduckgo.com/?q=Standard+specs+for+audi+a3&ia=web

Yes I can hear it now and it sounds horrible, though I can not positively identify the noise. Possibilities to examine are: loose timing chain (if you have one), broken exhaust mounting, worn bearing in alternator or water pump or power steering pump, worn turbo (if you have one).

Sorry Thodoris, but even at maximum volume the sound is quiet and I hear nothing unusual.

No it is not normal for the lamp to illuminate at all. I echo Steve's recommendations.

Andy. In the past year or so there was a post here from somebody who repaired his door wiring. Search through the forum history to find it.

I have no idea what a stage 1 cr170 is, but if it is a tuned engine then Steve is right, the revs are too low. Generally the more tuned an engine is, the smaller the power band. Most road cars are designed to deliver power over a wide rev range for maximum flexibility, but if you modify the engine for more more power you sacrifice some of that flexibility.

Get your battery tested before doing anything else. It does not matter if it starts the engine satisfactorily, it can still have an internal fault which can interfere with the car's electronics.

I will not argue the economic or thermodynamic aspects of ethanol addition to petrol, but as a chemist most of my working life I challenge the assertion that ethanol is "extremely corrosive". It that was true it would be undrinkable, and given that ethanol is the active ingredient of all booze I don't see millions of people dying after a couple of drinks. Mankind has been making, pumping and storing ethanol for hundreds of years so there are no insurmountable problems in handling it. No, the fact is that ethanol is a different sort of organic solvent to the octane and related hydrocarbons that comprise petrol, and therefore requires different materials to be used for its storage, pumping, sealing, and injection. It would be easy to design and build a fuel system for ethanol, but our problem arises from trying to run ethanol in existing systems designed for petrol. It is similar to the situation when tetra ethyl lead (the anti knock additive) was eliminated from petrol many years ago. Older cars at the time suffered erosion of the valve seats because they relied on the additive to seal them; newer cars were designed with harder seats and have had no problems ever since. With regard to emissions from alcohol fuelled engines, there will still be some CO2 because alcohol contains carbon, though proportionately less than petrol. As for nitrous and other oxides of nitrogen (NOX) I do not know, because the generation of NOX depends on the combustion temperature and efficiency of the engine; high efficiency engines create more NOX than low efficiency.

It's probably the fob battery, they don't last for ever, and at less than a pound for a new one it should be treated as a cheap way of testing the fob.

Glad to hear it, and thanks for the report.

Please do let us know the outcome.

Ten to one you need a new battery. A defective battery will play havoc with the ECU causing strange faults and false warnings., even though the engine is running and the alternator is putting out a good charge.

To be fair, split gaiters are not in themselves causes for an MOT failure because they do not affect the handling of the car. It is only when the the joints lose their grease and dirt then enters causing wear that a failure is justified. That is the reason most MOT test sites warn of an impending fault by means of an "advisory" notice. The onus is on the owner to heed that warning to avoid an expensive repair bill, new boots being cheaper than new joints.

Gary. Not to gainsay any of Gareth's sage advice, but something to bear in mind with a private purchase is that you have little recourse if some major component proves to be defective; whereas a reputable dealer will either stand by any guarantee or be subject to legal redress. Only you can decide if you are willing to pay higher dealer prices for the sake of that extra confidence in the car. If you are not familiar with assessing second hand cars yourself you would find a competent assessor like the RAC would be very worthwhile.

Peter. Any work done on your car by an Audi garage during its existence will have its history centrally recorded, so it should be possible to find when and by whom the sensor was fitted. If you have had work done to it by a non Audi garage there will be no such record.

Please do let us know the outcome. The information would be invaluable for future reference.

Thinking further on the matter, perhaps speculating further would be a better description, if the problem is outside temperature dependant I would investigate how and where that temperature sensor affects the ECU. I reckon there must be an temperature input to the ECU so that it can compensate for ambient air temp variation, but the details of how that circuit operates are beyond me. I suggest an auto electrical specialist would be the best option at the moment, because I have been distinctly unimpressed by reports I have read on this forum regarding the diagnostic abilities of even Audi main dealers. As I said before, if the computer says no, Audi are stumped.

Adrian. My first thought was the instrument cluster but as you have had that changed I am at a loss to think what else it could be. Did Audi have any suggestions, or did the problem not happen while the car was in their hands? Sadly the reliance on diagnostic computers has eliminated the human brain as a means of tracing car faults.

If the rubber boots were split ten months ago the joints they cover will undoubtedly be ruined by now and have to be renewed. It would have been much cheaper to get them fixed when the problem was first found. To get an idea of that cost, pick up a phone and call a garage.

Tell us the bite point of the clutch. In other words at what pedal height does the clutch start to engage? If it is much less than half way up you have a clutch problem.

You have not mentioned what sort of gearbox it has, but assuming it's a manual transmission the problem is most likely a worn clutch. When was it last changed?