J.R.

Are you not psychic?

In their defence they are unlikely to tell you to regularly charge your battery because the invasive VW computer has given you the slow puncture or high pitched grinding noise that you are concerned about.

You need to drive faster to eradicate the problem.

It will be the brake backplate (I am assuming that your car has rear disc brakes), you dont need a garage to check, you have said you can see the rusty item, give it a poke with your finger between the alloy wheel spokes.

I only offered a suggestion for the MK1, what I thought the OP owned from his profile, on my computer screen I cannot see which section I am in and I am also partially sighted so when I read text what is around it does not register, so whilst the info may have been there to a fully sighted person when I clicked on the topic it may not have been visible to me, to compound matters I also have close to zero short term memory, I'm sorry that I have upset you, it was not my intention, I regret that you consider me a pedantic thing 99% of the time. Regarding the traction control function it depends on what model of ABS controller is fitted (MK60 rings a bell?) and from studying the subject because I felt my MK2 was so poor compared to the MK1 I found that some models but not mine had the better ABS controller fitted as standard so it is not a black & white MK1 or MK2 subject and my suggestion could have been relevant to the OP but I see that he has now confirmed the grating happens when pulling away gently.

Rusted out fixings on the rear brake disc backplate. Well not the fixings but the plate around the fixings.

There are no universal joints within a CV, if there were then it could not be called a constant velocity joint. To the OP, are you pulling away on partial lock with a bit of enthusiasm? At a T junction perhaps? One of the characteristics of the traction control system on my MK1 Octavia that always used to grate with me (pun intended) was that when it applied the brakes to the wheel losing traction it gave a horrible graunching transmission noise, appalling to the ears of anyone with mechanical sympathy and knowledge like yourself and I could indeed feel it through the pedal box but also through everyone of my nerve endings. By comparison the MK2 just cut the throttle and would leave me exposed when pulling across a regular junction in the wet where the MK1 would have got across quickly but put my teeth on edge.

Fuel guages since time began have always been pretty useless, that said after doing some checking in VCDS the fuel capacity calculated by the ECU from the resistance of the sender unit, two sender units in the case of my vehicle is remarkably accurate over the entire range which is some achievement when you consider the geometry involved, clearly the algorithm compensates for the non linear swing. If only the information sent to be displayed on the fuel guage and the Maxidot were as true and not fiddled with to create the virtual reserve capacity. Given that the primary concern for most of us is not how full the tank is but how far from empty I much preferred the very old undamped fuel guages as long as I had tweaked the float lever to touch the bottom of the tank, the rest of the guage travel could be miles out but I knew that when it read zero and no longer flickered when I threw the car around corners then it was taking its very last sip of fuel!

There is probably a bit of stiction on the float lever and also the hysteresis of the potentiometer and the damping of the fuel guage but as I said it is pointless relying on either the guage or miles remaining indicator beneath 3/8 of a tank of fuel.

Its the virtual reserve that is created by the program that converts the sender reading to the fuel guage and maxidot display. A full tank shows as a full tank and the expected range is as it should be assuming your journey or driver profile remains constant. It is still true at half a tank, from 3/8 of a tank onwards it gradually reduces the indicated tank level and miles remaining to create the "virtual reserve" of 5-7 litres when the fuel guage and remaining miles show zero. You cannot rely on either display when you are maintain a very low tank level and top up with small amounts. I tested my MK2 Octavias ultimate range and drove another 70 or so miles before running out, I put in 5l from a jerrycan, the sender is really accurate as it registered on the fuel guage and the remaining miles went up to 20 I drove less than a mile to the nearest filling station during which time the remaining miles dropped to 15, then 10, then 5 then zero.

You use the phrase "slam to a halt", that indicates to me an emergency stop, you say your ABS cut in and reduced your stopping distance to "virtually non existant", are you actually saying that the car stopped quicker than you wanted it to? Maybe I have misunderstood, you cannot have it both ways, slamming on the brakes but actually wanting to slow progressively, maybe you meant that your stopping distance increased to virtually infinity? You have variously described that your ABS has cut in at 20-25mph, 15-20mph, 15mph, 5mph and 5-10 mph and braking harshly, hitting the brakes harsh, slammed the brakes, slam the brakes, slam harshly on the brakes, pushing the pedal to its limits, pushing the pedal to the floor, slam to a halt............... In my experience under every one of these combinations of speed and heavy braking the wheels would lock and the ABS would cut in to recover the driver induced skid situation, I cannot understand why you believe that it should not or would not. I can only repeat what I suggested earlier, that trying a more modulated approach is the way to sho whether the system has a fault: "I suggest he trys braking gently and progressively to a halt in dry conditions, if the ABS cuts in which would increase the stopping distance then something is amiss, otherwise the vehicle is doing what it says on the tin." Alternatively follow another suggestion and remove the ABS fuse and stick to your slamming on the brakes régime but please ensure nobody else is around at the time, without the ABS the brakes will lock very easily and create surprising instability, I know this because once my ABS warning light came up (it was a battery fault) and I tried harsh braking from 40mph to see if the ABS was operational or not, it wasn't and without it the brakes were very overservoed, lacked feedback and locked very easily.

How were you proposing to fit them without using a jack?

Have you never driven on snow or ice? If you did your emergency stop for real at under 10mph in those conditions you would soon be complaining that the ABS should have cut in, except you wont because it will have.

He is stamping on the pedal, he is doing a full blown emergency stop at 5mph (probably more) a speed where the wheels will easily lock up trying to stop the momentum of over a tonne of vehicle and then complaining that the ABS cuts in because he thought it was only supposed to work at higher speeds. I suggest he trys braking gently and progressively to a halt in dry conditions, if the ABS cuts in which would increase the stopping distance then something is amiss, otherwise the vehicle is doing what it says on the tin.

Are you declutching when you do these emergency stops? I know its contra-intuitive but you must learn to do this during an emergency braking manouvre to allow the ABS to work effectively on all wheels, you also have to learn to steer during the manouvre, again counter intuitive but the ability to do that while emergency braking is the raison d'être of ABS. Its not apparent at higher speeds but at low speeds if you dont declutch the anti-stall feature of the ECM will be fighting against the brakes, a graphic example of this were my Sierra XR4x4's of the late 90's, playing in a snowy car park an emergency stop when declutched would have a longer stopping distance than on dry tarmac and with loads of ABS oscillation, doing the same without declutching resulted in the 3 litre V6 engine surging and the car just pushing on against much reduced ABS intervention ad infinitum, it would never come to a stop until declutched.

Descending a hill in gear with no throttle is not coasting. Doing that in a high or low gear makes no difference to the fuel consumption because as long as the engine is doing more than +/- 1200 rpm no fuel is being consumed. Which creates a strange dichotomy, usually coasting (proper coasting) in neutral downhill is the most efficient as the more speed you can build up without engine braking the further it will carry you along the straight or up the next hill, however the engine will be consuming some fuel while idling whereas if you were in gear with the throttle closed no fuel is consumed. I coast downhill (out of gear) unless it is going to take me above the speed limit and there is a camera, if I am baulked by a car in front i put it back in gear to save the little fuel, on a hill where I know I have to stop at the bottom for a junction or slow down for a 30 limit in a village etc then I will descend in gear.

I don't like them from an engineering standpoint, and in those terms they are definitely a bodge, there are much better, appropriate, even elegant solutions out there. Grayston make helper springs, a secondary coil spring that fits inside the existing one, I used them for 13 years on my MK1 Octavia and they were great, they are also simplicity itself to fit, as easy as changing a rear spring which is dead simple. And on that note, had I known then about the range of springs fitted, their colour codes etc and also just how much the OE springs sag with age I would have fitted new uprated versions from Lesjofors which is what I have done on my MK2 Octavia and the Yeti. It sounds like the OP's springs are already sagging, fitting spacers between the coils really is not a good idea in that instance, the springs once sagging break rapidly enough on their own without assistance, all of my Skoda have had multiple broken springs, touch wood the Lesjofors replacements have not to date. There are aftermarket "airbag" type spring assistors that can be inflated up for towing, I never found anything available for my Octavias or Yeti though, hopefully someone will know different. Finally the best I have ever experienced, the simplest and most user friendly came as standard on all my Sierra Estates (in Ghia and 4x4 trim) they had Boge self levelling struts, I think they were integral with the rear dampers or maybe it was seperate, they would "pump up" with the spring deflection when heavily loaded or in my case suicidally overloaded and bring the car back to level, I could load the thing with concrete blocks, bags of sand, cement, whatever until it was dragging its ar5e like a dog with worms, right down on the bump stops, drive it a few yards over a few bumps and it would come level again, also the suspension was never stiff or harsh loaded or unloaded. Its a shame no manufacturer fits them nowadays or that they are not available as an aftermarket fitment.

They are meaningless, had they measured and reported the run out using a dial comparator it would have been worth something but thats well beyond the competence and comprehension of a modern dealer. Your discs will not be warped, even they are not saying that, they say they are "blurred", tell them to go to Specsavers! 1st rule is to disbelieve everything they tell you, then you wont be going down blind alleys looking for imaginary mechanical issues that cause disc warping, even my fertile imagination cannot dream up one that would have that effect.

F***wits cannot even stringa coherent sentence together. I suggest they meant "blueing" and would also suggest the discs are anything but blue and the cause is not excessive heat but too gentle application of brakes which is to be commended but the modern pad materials dont like it. Here is what I posted yesterday on this very subject:

A safety related item, unless there is evidence that it has been abused it should be replaced without question. Did VAG not once have a recall for rear centre belt buckles on some vehicles? I recall them recommending that a passenger should not be carried in the centre position and thinking many families would be insisting on loan vehicles.

Drive it down a long fast steep hill at high speed doing consecutive emergency stops until the pads are smoking and the ABS will no longer cut in, then drive carefully home avoiding heavy braking or any braking if possible, leave parked in gear with the handbrake off. Next time you drive the judder will be gone and the brakes will have much more bite. 40 years ago whenever I visited my retired father in Cornwall he would say "can you do your thing to the brakes again son?" the handbrake on the Polo had a very coarse ratchet and he could only pull it on 2 clicks after a while it would not hold and usually the brakes would be juddering, it only happened on vehicles driven very smoothly and the brakes rarely solicited, now I am his age and no longer drive like the road is my personal racetrack I have to do the above to my own vehicle. I bought a Galaxy once and the brakes were appalling, really scored & grooved & the juddering would tear the steering wheel out of your hand, my first job when I had the time was new discs & pads all round, in the meantime it was pressed into service going to and from sites carying all my tools & driving like the lunatic that I was. After a week the juddering had all but gone away & the brakes were responsive, after 2 weeks they were perfect and to my surprise the scoring and grooves had dissapeared, they looked like freshly machined discs.

It looks like it is intended to get hot because the conformal coating or whatever it is called has been masked in a square around it. I have repaired several electrical appliances (well bodged by removing a questionable safety device) by shunting a failed "thermal fuse" the items have been a coffee maker, a steam mop and an electric blanket, in all cases the fuse was designed to fail if the appliance was left plugged in and heating for an extended period, in the case of the electric blanket the fuse was squeezed between two thermal resistors whose job it was to heat it to failure if left plugged in overnight. From your description it was my first thought but could it perhaps be some sort of temperature compensation for if the instrument cluster gets heated from direct sunlight?

Dont disturb the ECU, there is not a better protected connector known to mankind. Start looking for the cables the mice have chewed through

Do you know this or were you advised by the garage? If the latter then check the part number to confirm the veracity of the information before starting any invasive procedures you may regret.