Breezy_Pete

Good work and useful feedback, well done. 🙂

The grey/white wire on pin 7. 🙂

Your car has the necessary k-line connection to the diagnostic socket socket. As do all mk1 Fabia and mk2 Fabia pre-March 2010. I think Roomster probably also has until March 2010 as it is basically the same car as Fabia. I started a thread about this in mk2 Fabia forum and some people confirmed that it works.

Yes, exactly that.

You'll probably need a beefy puller to break the bond if it's never been apart before. Something along these lines https://www.ebay.co.uk/itm/35https://www.ebay.co.uk/itm/354725649411

I think the freeware version of VCDS will work on your car with a suitable, cheap FTDI interface cable. Download VCDS Lite from ross-tech.com and buy a suitable cable from ebay etc for <20 euro.

Oil pressure switch connects to instrument cluster, not ECU. ECUs are generally massively more reliable than wiring looms.

If the oil pressure switch is physically located anywhere near the intake flap valve, look carefully for wiring damage in the loom, possibly caused by moving stuff around during cleaning operations. Pressure switch has a single black wire connection.

Don't think mk1s ever had the BZG engine, so mk2.

Message me your VIN and I can check it for you.

FWIW I can't see any gaps listed in the erWin Fabia mk2 workshop manuals (maintenance nor engine-specific) so Haynes probably just carried forward their info from the mk1 manual when they couldn't find anything else to write. Do you happen to know what your fuel pressure is regulated at? May be stamped into the end of the filter just in front of offside rear wheel. I recently discovered that some of the later mk1 HTPs (some if not all BME 12V engines) got 4 bar regs instead of the original 3 bar. May also be true of the BZG. Could be relevant to spark gaps, I guess?

For the mk1 HTPs the gaps are different for different plug manufacturers, what's listed for mk2, did you say somewhere? Sorry, yes, you did in the first post. What gap did they arrive with?

I tend to disagree, having looked a the stub axle itself (item 11), which has a tight M16 bolt through the middle of it holding the bearing when in service. doesn't look at all likely to bend, according to my amateur structural engineer's gut. This is one such piccy. There's an M16 bolt up the middle of it holding the bearing on, just seems really hefty as an overall chunk, but possibly still worth checking before going for full rear beam swapout:

Always nice to find something about your car that can't ever cause a problem. 🙂

Not sure diesels have them?

Dunno; what's a power probe and can it measure dc voltage? I have this vague recollection that I've seen mention of a 'repair loom' for this section of cabling (which suggests a frequent failure of sone part thereof). If you message me your VIN I can research whether it correlates with your car's age etc.

Stabbing through insulation of each wire with a needle or pin just above the cable entry grommets would be a valid alternative to possibly damaging the seals. Easily taped over subsequently. Make sure inserted items don't short to one another though!

If Andy would like to message me with his VIN I can look up hub part number for his car and price.

Unloaded voltage tells you nothing except that neither conductor is totally broken.

You could also confirm/deny whether the VCDS reported term 30 voltage at the pump is factual by measuring between the two at the pump connector, back-probing while active as above. Makes sense to do that before the above volt-drop tests, in hindsight.

The power wiring to the pump is the obvious problem here, not just the cleanliness of the connections. Not sure how easily you could back-probe the connections at the pump while plugged in and active through/past the rubber seals but that's what I would suggest. With multimeter on dc volts setting, go looking for that missing voltage by measuring along the length of the two big cables. Positive red connection at pump to each/both ends of the strip fuse it comes from, then from brown earth connection at pump to battery negative. Ideally with pump loaded at least somewhat by an assistant wiggling the steering wheel gently from side to side, engine running.

Message me your vin and I could look up part number and price new if still available.

Well, a control unit about the size of two normal relays, with pins that fit in those adjacent relay sockets.

Phone them with your VIN to hand and they'll be able to check better on the screen they have. Better info than on the website.

EGR cooler may be another possibility. Bypass it by joining the hoses that go to it, to see if anything changes?