cliffcoggin

Thanks for posting that William. It might help others with a similar problem. It's a shame Milos has not commented further on his problem.

I still don't think we have a full and accurate description of the symptoms, or the work that has been done, but from what I gather so far there is a hydraulic fault. Most likely air in the system, less likely damaged piston seals.

I'm not clear quite what you are describing. Are you saying the pedal moves up and down without you touching it, or do you mean the bite point changes from one pedal press to the next?

One possibility is a faulty spark plug which might cause the revs to drop so low that the anti-stall boosts the revs briefly to compensate, and you end up with unstable idling. That is a total guess but has a cheap solution. Another possibility is an air leak somewhere in the induction system. It might be hard to find if it is more than a split hose or loose connection.

It's right below the manifold <G> More seriously, I suggest searching for on-line car breakers if it is secondhand you are wanting.

I guess we'll never know the outcome as Darren has not had the courtesy to reply, or even acknowledge our responses.

I would expect she has solved the problem since it has been nine months from posing the question, but in the absence of any reply from Ann we can only guess.

The video shows a short engine (i.e. head removed,) that had had liquid poured into all four cylinders. Two pots still had liquid inside; the other two were empty. That to me is unequivocal proof that the bores and/or rings are worn.

Ouch! That must hurt.

Gareth. Watch the video. I think you will change your mind.

I agree with the diagnosis provided by Audi which is very clear: the low compression is a result of worn or broken piston rings, possibly also associated with worn bores. (The soot on the valve stems was caused by incomplete combustion of the fuel as a result of the low compression.) Three solutions occur to me: [1] Rebore and totally rebuild the existing engine. [2] Buy a new engine. [3] Buy a secondhand engine. Options 1 will give you effectively the same as option 2 in terms of performance and durability if it is done properly, i.e. a new engine. Reboring used to be cheaper years ago but that may not be the case now given the high cost of labour. Option 3 will be cheapest but the quality will be a lottery.

I have no personal experience of the matter but it strikes me that the on line repairers offer fast, cheap and guaranteed repair, while a secondhand unit would only be cheap.

Personally I would fit a new solenoid for no other reason than I dislike the sticky staining of WD40, but then I have a particular hatred of the stuff. It would be worth first testing the fuse and electrical supply if you can. You may already be aware that WD40 is not, and was never designed to be, a lubricant. It was the result of many tests of various mixtures whose purpose was to drive water from the surface of wet steel in order to prevent rusting. The winning mixture was the fortieth mix tried, hence WD (water displacement) 40. It's true that it contains a mineral oil, but the MSDS reveals it also contains an organic solvent similar to paraffin and a perfume to cover the stink of that paraffin. As the solvent evaporates it leaves the oil and the perfume residue which, as I mentioned earlier, leaves a nasty sticky mess.

WD40 may be fine for a temporary fix, but it isn't a good long term solution as the oils in it will dry up leaving a sticky residue.

Search for online car breakers. I bought a head rest for £30 including postage from one of them and it was an exact match to the existing rests.

Sorry Ed, I can not advise without information, and the only way I can get that information is if you provide specific answers to the questions I posed. The fact that the clutch is new does not eliminate it from the problem, because even new clutches can fail or be wrongly fitted or suffer hydraulic faults. Only once we are sure the clutch is fully functional should we consider other possible faults with the gearbox.

And the bite point?

Ed. My first suspect for all gear engagement problems is the clutch. Is the bite point at the top, middle, or bottom of the pedal travel? Does it grab smoothly or is it sudden? How many miles has the clutch done? Is the fluid level (assuming it is hydraulic) low?

Incompetent or not, the dealer is responsible for the warranty until it expires. Whether that means he has to do the work or only pay you for getting it done by somebody else under Australian law I have no idea, but if you don't complain now he will always have the excuse that the fault arose after the warranty ran out.

John. There is a Youtube channel by a John Cadogan that I regularly watch and by chance I happened on this video on DPFs. It may give you some hints on what is causing the frequent regenerations. Be warned, his language is satirical and often laden with expletives, but he is very knowledgeable. In essence DPF problems can be caused amongst other things by: -inlet air leaks, -faulty injectors, -insufficient sustained high speed operation, -the wrong oil. https://www.youtube.com/watch?v=-bOlDFFhuPM

Well m is the standard abbreviation of metres which makes more sense, but the text distinctly states kilometres. As for the rest of the report. I don't see that it tells you anything you didn't already know i.e. the engine is making lots of soot. What it does not tell you is why. It would be too much of a coincidence if the problem was unrelated to running on petrol, so you need to examine and possibly test the fuel system from pump to injectors. I doubt that the average home mechanic would have the equipment to do that as I fancy it would need flow testers and and injector measuring tools. In fact I wonder if even Audi main dealers would be able to do that, or whether they would simply renew parts in turn until the fault disappeared. I frankly don't know what to advise except to consult a diesel specialist.

Tony. No matter what the cause you should get the fault registered with Audi before the guarantee runs out. Even if Audi then prevaricate about fixing it they will not be able to deny that it occurred during the guarantee period. For what it's worth I favour the turbo as the culprit, an expensive repair job and not something you would want to pay for from your own pocket.

Perhaps I am misreading the data but it appears to show that the last regeneration was 556045 km. ago. Whether that is related to running on petrol or not I have no idea.

https://www.prestigeimports.net/audi-dashboard-warning-lights/

Do let us know the outcome.