Breezy_Pete

Fair enough. If you have any further trouble, it's probably not too hard to get to the source of these wires beyond the holes in body and tailgate, and replace the sections which go through the bellows, with splices in areas that don't flex when the tailgate is moved.

I'm not convinced that super-thick black wire is an original part of this car. Might be a 'this is all I had' repair bodge previously. Can you not take the tailgate trim off and see where it goes to?

Yes, probably the only temperature sensor, communicating initially with engine ECU, but then that data being shared to other modules like the dash panel. There is often a thermoswitch, in or near the radiator that controls the radiator fans, but gives no numerical temperature to any modules. I can look up more info about your car if you share reg or VIN. But not just now, about to be driving for a while.

Have you bought that part that you've shown on deutsche-parts.co.uk? Which part number did it match, the original -AN or the superseding -BA? The end fittings all look fairly straightforward to me, from what I can see, so probably a pretty easy fitment.

EGR operation actually tends to increase particulate emissions (which is measured at MOT; the only emissions measure for diesel cars), but it decreases nasty, poisonous NOx emissions (which isn't measured at MOT). Sounds like your car is emitting a whole lot more of something when EGR is active, so you're probably doing everyone a favour by temporarily disabling it; but yes, do it subtly, and don't whatever you do discuss illegal stuff on the internet! 😆 Get the fault diagnosed properly, then you should be able to re-instate the factory emissions set-up. White smoke on diesels is unburnt fuel, I think? That should be a clue, but I know next to nothing about diesels and what goes wrong with them.

Until I looked at the wiring diagram this morning I had no clue this car had any such thing. Bloody modern nonsense. I actually tried briefly to disable the whole seatbelt warning system with VCDS, but it didn't look as simple as a youtube video seemed to suggest, so I bottled it for fear of knobbing something else up. I mean, what sort of idiot needs reminding to put their seatbelt on in 2025?

You don't actually. Your car is early enough to be exempt from this requirement. From the MOT manual: 8.2.2.2. Opacity Engine malfunction indicator lamp (engine management light or ‘EML’)Turn on the ignition and check that the engine malfunction indicator lamp (MIL) illuminates and then goes off. On some vehicles it will be necessary to start the engine before the MIL goes off. You need to inspect MIL fitted to diesel vehicles including hybrids with 4 or more wheels and first used on or after 1 July 2008. [My reddening of the red bit] MOT inspection manual: cars and passenger vehicles - 8. Nuisance - Guidance - GOV.UK You probably do need to disguise the fact that the vac hose is disco'd though, otherwise it should fail on modification or disablement of an emissions system.

Great info, especially the weighing thing. 🙂

A spare Roomster steering knuckle inside a large zip lock bag will do it, especially when near the outside edge of the seat towards the seatback. A bottle of red wine on the inner edge isn't enough, but if you press down on it it a little, it is. 🤪 Thought of you yesterday, Lee. Had a team of Openreach wiremen digging a hole in the pavement right outside our house. We don't have a landline any more, but they seemed to find and fix the problem and refill the hole pretty efficiently. Blamed it on Virgin Media's fibre installers, who'd been very much in the same spot recently.

I was so close to trying to chase a phantom wiring fault from under driver's seat towards the airbag module where these wires go. That would've driven me more bonkers!

I knew a 2012 car was going to be too clever for me! 😆

That's great, thanks @Robjon . I experimented on the way home with variously heavy items in various positions on passenger seat. Doesn't take a great deal of weight. Problem solved, I think. :)

Yep, AKF valve is the German abbreviation for purge valve. Pretty sure the actual purge valve is the grey bit we identified above. Bit of an expensive parts-cannon guess, by the looks of the pre-VAT prices.

Via a tester plugged into the spot where the pressure switch is, according to the criteria I listed in your other thread. Unfortunately there's no guidance in the workshop manual about what should happen in between the minimum and maximum criteria, except by inference that it should rise towards 5 bar with rising revs, but no clue about what is 'normal behaviour'.

I doubt it. Did you try measuring pressures at operating temp?

Have any Roomster owners experienced what appear to be false warning bong/light relating to seatbelts? Have been chasing down what I assumed to be an intermittent fault with the receiving latch for driver's side front seatbelt. Had the disappointment yesterday of fitting a 'new' latch only to have my partner report that there was one brief instance of the 'bong' warning on the very next journey. Whilst looking at the wiring diagram this morning, with a view to eliminating the green connector pair under driver's seat, I noticed that there's an asterisked option of passenger front seat belt latch sensing, together with an occupancy sensor - G452 Pressure sensor for seat occupied recognition. Checked the car and it does have wiring from the belt receiving latch, so it appears to have this option. Now wondering if the occasional false triggering is actually being caused by bags on passenger seat? No such occupancy sensor on previous cars, so we habitually do put bags there. Apparently there was a fairly heavy bag there on the trip yesterday evening. Anyone experienced this? Thanks for any feedback.

Can't see clearly enough from those pics, maybe one can just about see a connector and wire hanging down in the first pic, under the black pipe that's coming out of it going rightwards? If you supply reg or VIN, I can look up part number for you.

If you go to erWin Skoda and register an account (free to do so) you can then click on the link a little below the register button on the homepage and view ">Approved oil types". Amongst the list for 504/507 oils that have been tested and approved by VW group, there is a fair proportion (maybe 30%?) of the oils in the long list that are 0W30 rather than 5W30.

Does the grey thing have an electrical connector? Looks the right shape for a purge valve. Is there a part number visible on it? I seem to remember the purge valve on recentish models tends to come with a whole gubbins of pipework as an assembly with an overall part number. It looks rather like that grey one is 'plumbed into' various other bits without being easily separable.

Correct, main chain has hydraulic tensioner, oil pump has a more basic 'springy bent bit of metal' tensioning arrangement for its chain, I seem to remember. The deep-tone knocking noise sounds quite worrying, if that's the one the video is trying to demonstrate. Not sure what might cause that. How many km has the car travelled?

@schmooser there are three oil pressure switches on this engine: 04L919081, a green one rated 0.3-0.6 bar, 03N919081, a grey one rated 2.0-2.7 bar, and 04L919081B, a brown one rated 2.3-3.0 bar 1st and 3rd are as you thought in your opening post. I vaguely recall two of these being close to one another, and the third elsewhere, not as easily spotted.

I'm not familiar with the terminology HDI, not a VW group description I think. Assuming it's a 1.6 CR TDI, the workshop info suggests the following test criteria (with pre-condition of coolant temperature at 80° minimum): Oil pressure when engine idling: min. 0.08 MPa (0.8 bar) Oil pressure at 2000 rpm: min. 0.15 MPa (1.5 bar) Oil pressure at higher engine speed: max. 0.5 MPa (5.0 bar) The last one of those is perhaps the only one that is questionable on your engine. Try it again with engine at full operating temperature (after a run of say 15 minutes plus). The oil pressure switch that you have tee'd into cannot give a numerical pressure reading to any control unit, it's just open or closed circuit switch to ground, so no diagnostic readout of oil pressure is available through the car's native systems.

Your shock absorber part number is just about visible on the sticker, 6Q0413031BJ. Again, the letters make all the difference among the variants.

The paint dots are VW group's way of identifying unique spring part numbers. Same springs on the front of our Roomy, genuine part number is 6Q0411105AG. Don't fall into the common trap of thinking the letters at the end don't matter much. In this and many other cases, the letters are the only differences in the part numbers amongst all the different variants of spring.