J.R.

Do you have a source for that or was it mechanics talk? EGR may reduce combustion temperatures but the ambient air that it replaces is also much cooler, modern valve materials were more than capable of withstanding combustion temperatures before EGR reduced them under certain limited operating conditions in any case EGR is supressed whenever a DPF regeneration is in progress to increase the exhaust gas temperatures, the exhaust valves can cope with those temperatures all day long. Burnt exhaust valves are something from 50 years ago before ECU controlled fueling and ignition.

A software change cannot bypass an EGR, it's physically impossible. It may prevent it from functioning, the EGR emulator/simulator on my vehicle does that, a company that misrepresents a product they offer rings warning bells with me. I'm happy with the emulator solution because if one day it causes problems with the ECU I can very quickly and easily disconnect it and revert to the standard set up, the ECU programming has not been changed. Well actually it has subsequently because I had a performance remap, I come from a long line of hypocrites!

Then AFAIK you have the problematic concentric slave cylinder. Give it time....................................

Glad to hear that at least one garage somewhere is not ripping the ar5e out of their customers!

Apologies, now my eye (singular) can see what you mean, one of each pair of guide pins has a reduced diameter shaft with a plastic bush. I am considering them to be pairs as the kerbside ones are rusty and the offside ones are shiney. I never remove the pins and simply partially withdraw them making sure they are not seized so have never encountered the bushes.

You ask why one of the pins is "coated in rubber" then ask why only one of the pins has a rubber sleeve, if the other three dont have sleeves then you have yourself answered your first question and the answer to the second one is "because!" Never in my lifetime will I waste money replacing perfectly serviceable guide caliper pins, is it perhaps the only way to buy new bushes?

Yes it does! The shorter answer is "because!"

Its ripe for a remap if that floats your boat, a cheap no risk option as well if you buy a pre-installed map on a second hand ECU (E-bay is the place) they call them "plug n Play" remaps. Then you get to keep the original ECU as a spare, I know that you like me understand that ECU failure is as rare as rocking horse poo but having a spare one can rule out the possibility when fault finding. 2 minor downsides to using an ECU from a probably scrapped vehicle, to mak it plug and play they disable the immobiliser, that for me was actually a positive, one less common fault to occur and no-one is likely to try stealing my vehicle, the other one is that whilst your odometer will continue to show the correct mileage the check mileage function on VCDS will show the one stored on the ECU which will be a 50/50 chance of being higher or lower. That said that function is not available on the Yeti ECU and may not be on your A4 either. It looks a nice package, I'll definitely consider one if something happens to the Yeti, EU4 emissions and the best of the PD engines sounds like the sweet spot to me, does it have a 6 speed gearbox as well? Thinking about it a torquey PD engine does not need an additional gear ratio.

Because like the others it slides in rubber bushes, its quite normal for some to transfer to the pin, I would not describe that as "coated" and I can see similar traces on the other slide pins.

They are self composting, actually I hope it should be "were" self composting as touch wood the Yeti one is still intact.

Yup, it has all the same failings (well minor irritations really) as my PD engined Octavia had! Mine also had an annoying buzzing rattly resonant vibration at certain engine RPM's which I eventually traced to the plastic insert in the engine cover, the one that supposed to suggest rippling abdos or intake tracts, it had movement on the plastic clips, a dollop of painters mate which was to hand at the time between the parts shut it up. I have yet to have a thermostat fail but have had a couple get blocked partially open by debris/foreign objects, it only takes something a mm or two to prevent warm up, in anything but tropical temperatures the stat barely opens off its seat, one of mine was blocked by a woodshaving/chipping, the mind boggles as to how it got in the cooling system.

I had not seen Petes post, mystery solved, do not try my suggestion, remove the old part first.

I have no experience of that particular filter but perhaps I could make a common sense observation.................... The male threaded protrusion has a hexagon inside suggesting to me that it can be removed for use on engines like yours which requires a female threaded filter or left in place for those requiring a male threaded one. Another possibility is that the mating face on the engines filter housing has a male threaded "nipple" (plumbing term) which should remain in place but perhaps sometimes gets unscrewed and thrown away with the old filter so the manufacturer includes the part with the replacement filters. Playing devils advocate if the above is correct I would have expected the nipple to have not been pre-fitted to the filter but I suspect packaging constraints dictated that it should be to prevent possible damage in transit. Try seeing if your new filter will fit after removing the part.

Not aimed at yourself but parole like that usually being spoken down to me in a condescending manner from someone who has never ever worked on their own vehicle makes me all the more determined to prove them wrong (if that is the case), you will no doubt have seen me triggered a few times on this forum (usually ABS sensors or brake discs) where I end up posting that I have fitted mega cheap Chinese parts without problem but boy oh boy did I bouffer mon brin when it came to coolant temperature sensors When the CTS played up on my MK1 Octavia I fitted a second hand one from a breakers yard engine, big mistake as all the factory fitted ones would fail (there was a certain colour that I should have sought) then a dirt cheap Chinese one only lasted a short while, the correct coloured VAG item from TPS did what it should do and continued to do so. I have never had a problem with a pattern part thermostat and as Pete wrote its one part where you can easily check that its working correctly before fitting and being mechanical are very robust in service, no electronics with underrated electrolytic capacitors etc to fail prematurely.

Your battery does not need to be insulated from the elements, any protection that a cover provides would be from underbonnet heat. They are simply an aesthetic thing and I understand the desire for that, the exposed battery on my Yeti looked really odd surrounded by all the other covers and compared to its predecessor my MK2 Octavia which had the factory battery box and cover. After carefully checking the battery tray which I reckon will be the same on your Superb I was fairly sure that the OE battery box and cover would fit, they are dirt cheap from Ali-Express and are genuine VAG parts produced in China for the Asian market vehicles, it fitted perfectly.

Sorry for the delay, I took a break from the forum. The thermostat is not an on-off device that triggers a spring, it operates gradually and linearly over a relatively wide temperature range. The thermostat is held shut (no coolant flow) by the spring, the spring is opposed by the force exerted from the wax capsule which expands with temperature. As the engine warms up the thermostat gradually opens allowing coolant flow, as the temperature continues to rise it will become fully open by the rated temperature, say 88°c, in a healthy cooling system that will only happen in extremis, towing up a hill in hot weather etc, normally the orifice will be partially open to maintain the regulated 88°c. There is actually some coolant flow when closed, there will be a metering hole with a jiggle pin to stop it becoming blocked, that way the warming coolant can reach and pass over the wax element, if this flow does not happen the engine will initially overheat before the thermostat opens through conduction of its metal body and then the temperature will fall before being maintained at the 88°c.

So I am a guff spouting loser to you then, good to know where I stand, I won't reciprocate.

Me too. I bet you didn't commute to work for 2 weeks in FWD (4WD engaged) only with the propshaft removed though! The 84 Shogun I moved up to had auto-reverse front freewheeling hubs. You could really feel the difference through the steering when the front driveshafts were turning and when they were not.

Does the Jimny have a centre differential or is it simply a later iteration of the LJ80, SJ410, SJ413 bloodline? Without one you should not engage 4WD on dry tarmac as I'm sure you are aware, the resultant transmission wind up can only be resolved by tyre scrub = increased tyre wear, the Haldex system has some nice tricks like momentarily disengaging the clutch (can be seen in live data) but the same scrub and additional tyre wear is there, people dont notice because with spirited driving the front tyres will indeed do more miles than on a FWD variant but the overall tyre wear across all tyres will be higher. That said I'm very pleased with having got 55k miles out of the last set, I could in theory have got a bit more on a FWD variant if I had avoided wheelspin but I would not have been comfortable driving in wet conditions with the tyres right down to the legal limit and beyond, with the 4WD it was a walk in the park.

Taxi driving is probably the kindest thing one can do to these diesel engines, my chauffeur pal put 188K miles on the MK1 Octavia he sold me after 3 years, I took it on to 325K miles and it still sounded like a sewing machine despite all the abuse and neglect it suffered in my hands. Pleased to hear you invested in the EGR device, its reassuring to be (fairly) confident that it is not going to go pop and give me a major job to do, its a real work up on a 4x4.

Wow, I'm surprised the alkies dont drink it, Vodka is only 40%. Are they perhaps concentrates for diluting? In which case I mislead myself. I simply could not imagine a screenwash reservoir containing 70-90% ethanol. I've been in France too long, here its all sold as diluted stuff in 5 litre containers at stupid prices, I have never bought any.

I had a concrete garage with asbestos roof for a couple of decades, it was frequently running with condensation. I fitted a pitched roof over my neighbours identical garage (they were both kits from the late 50's early 60's) he used corrugated steel roof covering, by chance I had used the same over a concrete garage in France and the steel was running with condensation so he found a breathable white barrier fabric which was placed under the steel and it worked a treat, for the fist time ever his garage was dry and the white reflects the light back down making it brighter. I have the same decision to make as you regarding my new 40m2 workshop, I think it is going to be timber framed, timber clad and the pitched roof will be tôle bac acier isolée - a double skinned steel corrugated roofing sheet with PU foam insulation between skins. It could even be used for the walls.

That has been the case with all VAG vehicles for 25 years now. You dont need a check light to tell you that the engine is not warming up to operating temperature, your toes under the heater duct will tell you that. As you do such a high mileage and presumably work full shifts I doubt your engine will have suffered any extra wear, certainly nothing that could be measured or even detected by oil analysis through operating at lets say 20°c below optimum temperature, it will have suffered far less wear, many magnitudes less than most vehicles whch are driven less than 5 miles each urban journey.

It may contain a small amount of Ethanol but the screenwash is not 70-90% alcohol.

Without a central differential it sure does. It will reduce the wear the front tyres see compared to a FWD model but the overall wear per unit distance divided by number of tyres will increase. Everytime I reverse out of a parking place on lock and feel the slight snatch as the pre-emptively engaged Haldex releases that is extra tyre wear from the 4x4 system.