cliffcoggin

Cant say for certain, but there's a good chance the tyres will rub bodywork at full steering lock or full suspension deflection.

You are right to be worried. Any knocking that loud should not be ignored. It's hard to be certain without hearing it from above and below the engine, and without using a stethoscope to locate the sound, but the most likely thing to my ear is a valve bouncing off a piston. I wondered at first if it might be a big end knocking but it doesn't sound quite metallic enough for that. Get it looked into immediately and it may only cost you a small fortune; delay the investigation and a new engine will cost you a large fortune. Sorry but it's going to be expensive either way.

If it is a cambelt engine, (I have no idea what the TFSI means,) ensure it has been changed. It's an expensive (£700) job to do but far more expensive if it hasn't.

I'll report back when I have it solved. Thanks for the confirmation gents.

That's a good point Steve, and for a moment I was cheered, but having looked it up it was actually the N/S/R lock that was replaced. O blow! (substitute expletive of your choice.)

Fair enough Vincent. I would take the car back to the dealer and let him worry about the cost. He should either fix it or refund your money.

Whatever the problem may be, and whatever the cost may be, surely it is cheaper to get it repaired before the warranty runs out.

I don't know about the legality of the work, but an undeclared power increase will undoubtedly invalidate the insurance.

It can be slipped in easily, and during turning the smooth resistance of a spring tells me something is moving. This is the door lock that Audi renewed a year & a half ago so I guess the switch is not connected or a wire has broken again. I'll look at it in the summer when the weather is better. I really only wanted know if the key ought to operate the lock before attempting a repair.

Thanks Steve. I'll add that to the list of outstanding jobs, though being a lower priority than paying work it probably won't get done. Ah well.

Last week the battery died in my key fob so the doors would not unlock. While awaiting a new battery I expected the key to work mechanically by pushing it into the key slot, but that did not work. (Fortunately I had a spare key fob with working battery.) Was my expectation wrong?

If power returns when you move the battery, either there is a poor terminal connection or the battery is defective. All the other faults may or may not be related to each other, but have nothing to do with the battery. The lack of error codes tells you nothing, they are in any case poor indicators of faults even when a code is generated, so I suggest you get it tested by a specialist auto electrician.

Glad you got it resolved. I am surprised the garage pressure test didn't reveal the leak from the EGR cooler considering how easily you found it after stripping the engine.

Do let us know the outcome James. Not just to satisfy our curiosity, but to possibly help others who may come this way.

Cliff.

Gareth. Surely if the thermostat was defective it would lead to real overheating which James says does not happen. I favour your approach to solving the problem by actually measuring the temperature with an independent device. I am not too impressed with the cheap infra red instruments, but the meters that have a contact probe are generally very good. Come to that, James could also remove the thermostat and test it hot water.

James. You imply, but did not actually confirm, that the engine temperature is correct while the gauge reading is wrong. Does steam vent from the header tank eventually? Can you smell any overheating in the engine bay? (Overheated engines have a distinctive odour.) If those signs aren't present, then the chances are that the sensor is faulty, but given the complexity of modern electronics on cars I would not be certain of it. Maybe an ECU fault can generate the fault. 

If you want to know what a main dealer would charge, ask one.

The only way I can imagine camber to be affected would be the wrong bottom arms, the wrong stub axles, or longer springs, but I don't know how to find the right part numbers. I am pretty sure different wheels would not change the camber.

Having said that, is it definitely the camber that is out, and not the toe-in? Excessive toe-in would cause similar wear to the outer shoulder of the tyres.

1 hour ago, Luey said:

Sorry if it wasn't clear I put the engine model in the title. It's a 2.0 TDI 170 (Engine code BMN).

So you did. Sorry, I didn't notice the TDI, though I must admit that many of the letters and numbers used to describe models by all manufacturers are meaningless to me.

A vacuum leak sounds a plausible explanation for the rough idling if you have a petrol engine because servo vacuum is drawn from the intake manifold. (Diesels have a combined fuel/vacuum pump for the servo.) Whether that would also explain an EGR problem I do not know.

What surprises me is engine fumes are getting into the cabin. Modern car ventilation ducts are usually well sealed from the engine bay.

As Gareth said, get it professionally tested if you can't be certain of precisely where the fault is. The trial and error method of replacing parts almost at random until the problem is resolved will cost a fortune. Once you have a definite cause you can decide whether to repair it yourself or get it done for you.

A neighbour who has a petrol A3 had a similar ridiculously high oil consumption without any smoke or leaks. An independent VAG mechanic and garage owner told her there was a fault with some of these engines which Audi was reluctant to admit to that caused the oil loss. He acted on her behalf in taking the matter up with Audi and got the problem resolved. I don't know the details of the fault or how it was repaired but it cost a lot less than the new engine that Audi originally advised her was needed.

I am normally too sceptical to believe such conspiracy theories, but she is a sensible character and not easily deceived, so I give some credence to the story.

I suffered what seems to be a common fault last week when the rear wiper motor erratically operated without being turned on, and then stopped completely. It turned out to be caused by blocked washer jets which blew out the seals and allowed water into the motor. (The water pipe runs inside the motor spindle.) Fortunately I was recommended to try an independent VAG repairer who not only fitted a new motor in one day but only charged a shade over £200 - a lot cheaper than a Audi main dealer.

The moral of the story is to keep washer jets clear.

Andrew.

I have no practical experience of the heating system so I can't advise further I'm afraid, though I do note that the link 

http://www.audi-portal.com/en/diagnostic/actuators_18918.html

mentions the need to bleed air out of the auxiliary heater, whatever that is.

Glad you're getting somewhere. I hope there's no aluminium in the matrix if you are using the caustic version of oven cleaner. (The less effective oven cleaners are just surfactants; the effective stuff contains caustic soda as well.)