Breezy_Pete

A loose battery terminal is the simplest explanation for symptoms like these.

Carefully grind a pair of flats onto the outside of the socket so you can spanner it round? Or molegrips straight on the socket if you have a pair that'll get in there?

This (or equivalent from another factor) is probably what they will fit, and they will likely get it for a little less than this: React Catalytic Converter (Front) | Euro Car Parts Might be an idea to get another quote for fitting only if you supply? I wouldn't usually recommend that approach, but the labour/sundries that gets you from £108 to £260 seems a little OTT. They'll also get a few tens of pounds by recycling your old cat.

It might be one of these - N 10104501 M7 x 18 12-point head. If so, try a 12 point 9mm socket for fit.N 10104501N 10104501 N 10104501

VCDS Lite with cheap FT232 cable. Then you get numbers that look like workshop manual stuff.

Or go to @Tech1e's uploads...

Here you go: Note 15 says 'for AZQ engine'

I will check the specs for the precat sensor in a little while, I think the expected number is quite strange, and your 1.299 is actually lower than it should be.

Can you see the output voltage of the pre-cat sensor?

So does this tool literally say "open loop operation" or "closed loop operation"? Or are you looking at pre-cat oxygen sensor voltage?

What measure are you using to distinguish between open and closed loop operation?

Can you see if there is a specific G62 temperature when it goes from misbehaving to being OK?

Small prize for anyone who can show a VCDS logfile with G143 maintained at any point other than fully open or fully closed. 😁

I'll have a look at those videos this evening if I don't have other stuff to do. I'll see if I have that SSP @J.R. The primary daftness with the recirc flap is the 'closing very time you select reverse' fanciness. Just serves to wear out the motor/pot/gears for such negligible benefit. Solved a problem that never really existed.

No

Probably the pulley, yes.

The odd thing is that even on cars with A/C, the recirc flap is still only ever driven fully open or closed - to the best of my knowledge - so there's never any need for potentiometer feedback really. It's only the warm air/cold air flap motor that gets actively positioned at intermediate settings (as far as I understand, can't say I've ever monitored/seen it in action).

I hadn't actually thought of looking for a part number on the pulley. I was going to suggest a much more indirect route of working out which 'version number' (leftmost column) alternator it is via this page: LLLParts Then going to this page (item 2, scroll down loads) to see which pulley part number suits the alternator version: individual parts; note: - Fabia(FAB) [EUROPA 2006 year] (7zap.com) Then see if there's any aftermarket cross-references in the extreme right-hand column corresponding to the relevant pulley part number. Still may be useful as a strategy if you can see alternator part number relatively easily (more easily than pulley part number).

Would need to know the part number of the alternator; does it have one in a visible position?

Well done. I think the level of movement needed to make an annoying noise is very minimal, and rarely possible to detect until the droplink is disconnected at one end.

Would fit an Octavia, but not a Fabia, I believe.

Have a careful look at your car. On ours the entire head is higher than the matrix connections. And the matrix is horizontal behind the connections.

You'll spill some however you do it, but if you can catch what comes out of the disconnected hoses with a big oil drain tray or similar, you shouldn't make too much mess.

Loads of stuff is higher than the heater matrix, the whole engine head for a start. If you park on a slope with the front of the car facing downhill, then disconnect the heater hoses at the firewall in the engine bay, most of the coolant will come out of the heater I think, as well as most of what's in the engine, so make sure you have plenty to refill with. Don't let any animals near any spilt fluid if you aren't able to catch it.

Any electrical misbehaviour may well relate to that dodgy earth cable/connection going to the strut top.