SuperbTWM

Yea thats a very good point, that quite a bit of coolant to be losing, its no wonder you saw noticeable wetness inside

You will get natural migration of water over time through the connection to the header tank but there is no flow as such in relation to the main cooling system as the system is designed to operate at much lower temperatures than the main cooling system

the coolant circulates as a sub circuit using the electric water pump and a seperate radiator. Somehow i don't think pumping 90C water round a charge cooler would do much for intake temps.

Did the tech put the K seal directly in the charge cooler loop? Although the charge cooler loop is connected to the main cooling system, there is no circulation between the two for obvious reasons. So if the K seal has worked, the liklihood is that it wasn't the charge cooler leaking.

Max voltage for pre start glow is effectively11.5V according to the manual but would you really want to try and power up something on the bench thats going to get to 1000 degrees in 2 seconds, I know I wouldn't Post glow down to 4.4V max

I think these reamers have been brought up before on this forum, not sure how I feel about breaking loads of carbon off inside the cylinders though. What has always baffled me is how short the glow time is on modern diesels but I have recently learned that aparently it takes just 2 seconds to reach 1000C

Which bit are you saying is the machined face? Only face I can see it sealing on is this one.

No not 100% just a gut feeling from past experiences (Last glow plug i changed was on a very primitive diesel water pump so it might of been that i was thinking of) but if you look at a glow plug there is no sealing face like you would see of a spark plug so either the thread or the threaded hole is tapered and seals by deformation of the threads or it seals further down the body in a conical seat type arrangement as they do seem rounded on the end. You seem to doubt the capabilities of a tapered thread?

Once the codes are logged they stay in the memory until reset so if it did trigger any they will still be there. Could of just been a one off or could be a clue that something electrical or with the fuel system is starting to die. Even with a fault code you can still be guessing, your better off just continuing to drive it until it happens again.

The weld on that looks very suspect, looks like its had a new core welded in the middle of it.

Presuming the sensor is working and the pipework is the right way round, the only way you should see a negative pressure is if there is an obstruction in the exhaust. On the latest diesels there is a electrically controlled valve in the exhaust to help increase EGR flow, does the petrol model have something similar which could have failed?

Own up, how many bits were leftover?

It must be falsely detecting something that is very close hence it goes straight for braking intervention maybe?

Mine also has this feature, basically uses the rear parking sensors to activate autonomous braking, doesn't half scare you if it picks up on a kerb. Never had any false alarms on the front though other than just warnings

Yea thats good, if its sat around the thread it has the best chance of getting pulled into the threads and hopefully reduced the chances of it shearing off. You may smell it as the engine warms up though

Whatever you do, if you drain the diff oil, remember to fill it back up before the test drive 😂 (sorry couldn't resist)

If you cycle the ignition can you hear the lift pump start reliably every time? out of say 10 cycles?

I hope you find your answer but as you describe garages and dealers never split the two apart, i'm guessing there is probably a good reason for this and I think you probably know the reason. I've also never come across a DIYer on any sort of forum that has done this either so it will be interesting to see more of the goings on inside a Haldex and teh rear diff. I vote you take one for the team and split the two for our interest 😁

You don't have to use VCDS, a half decent scanner will do the job to read engine codes, it might turn up nothing and leave you still guessing but it might also lead you right to the issue so its worth doing. I wouldn't bother checking the tandem pump to be fair, if its running alright the rest of the time that will probably be fine.

If there has been that much crap in the Haldex surely the next port of call after the pump is the controller, surely that has small oil passages and solenoid operated valves that will probably be blocked up. (i assume this model of Haldex doesn't have an oil filter like previous generations did? I get why a garage wants to fit a new one, because it will work after they have finished, you could spend hours of labor on this existing Haldex, it might work, it might not. If you don't want to get your hands dirty yourself then a new or recon unit is the way to go from a financial point of view

Was that not making any noise under braking? Thats pretty horrendous but not unual for 5 years, especially at low mileage

You checked the output of the Tandem pump? Have you hooked it up to VCDS to see if there are any codes, could be injector wiring harness or something like that

Lets not kid ourselves, it doesn't matter what you use, the penetration is always minimal and usually does very little apart from making you feel like your helping matters.

Depends on the bolt/stud but I would say you are more likely to pull the threads out of whatever the fastener it is in than shear it but it sure is possible with the lastest battery impacts these days, they are very impressive. I've got a Dewalt DCF899 and that is a beast, what i find more impressive though is my tiny 3/8" drive 12V milwaukee which will take wheel nuts off and a lot of suspension bits etc. really handy because of its size and weight.

IIRC adaptive cruise needs the long range radar, the standard radar for non adaptive cars is short range so cannot be done.