cliffcoggin

Do you actually need to know the size? Most motor factors only ask what model and year the car is to select the right part.

I'm not a diesel specialist, in fact I have had no formal training of any sort in car maintenance; I just learned the hard way over several decades of caring for my cars so make of my opinion what you will. The evidence to my mind points to the non-return valve in the primary pump not holding. I don't know how easy it is to replace yourself, (it depends on whether there is a access hatch in the boot floor or the fuel tank has to be dropped out,) but at £50 for a new pump I would take the chance rather than rely on the dubious opinion of specialists who are incapable finding the fault.

Well if the fuel system is OK, (and I'm not entirely convinced it is,) perhaps it's time to look at other faults such as engine compression, air filter, electronic control unit etc.

I've never heard of a hydraulic clutch becoming solid, so I suggest some diagnostic tests to find out where the problem is. [1] Open the bleed valve and push the pedal. If it goes down then the master cylinder is probably OK. If it does not you have found the problem. [2] Close the bleed valve, top up the reservoir, then disconnect the push rod from the slave cylinder. Push the pedal again. If it goes down then the slave cylinder is probably OK. If it does not you have found the problem. [3] If 1 and 2 are OK the problem must be the clutch itself, and it will have to be removed for examination.

It seems to be a common problem, though not one I have suffered. Why not fit a secondhand part? Many car breakers nowadays are on line and will post from anywhere in the country. It's how I got a replacement head rest.

The pipe is blocked and the seals damaged in the motor. See this recent topic: https://www.audiownersclub.com/forums/topic/12159-rear-wiper-motor-failure/

From a purely theoretical aspect, (having worked a bit in chemical engineering,) I would expect the pump to have non-return valves integral to its design. I would have a look while the pump is off the car.

I didn't know there was a time limit on the electric pump. Thanks for that information Dan.

If fuel is running back to the tank overnight, it would be worth turning on the ignition the next day and waiting 30 seconds for the fuel pump to pressurise the injectors before cranking the starter motor. It won't get rid of all the air but it will ease the load on the battery.

Ann. I assume you mean the door won't unlock rather than being physically jammed by crash damage or the like. If the other doors work then the chances are that the driver's door lock has failed. If none of the other doors operate then the central locking system has failed. Either way there is little you can do yourself unless you are handy with tools.

See this topic I started a couple of years ago. A forum search would have revealed it quickly.

Those diagnostic tools are not infallible. Who carried out the diagnosis? A friend with a reader, or an Audi agent? One might expect a professional would be competent enough to resolve the problem without the electronic diagnosis, but experience suggests otherwise.

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.