Breezy_Pete

The first two fault codes you mention are related to the accelerator pedal, not the throttle body. I would look for wiring damage near to the pedal connector.

I'm pretty sure you don't and shouldn't have a smart alternator. The car doesn't have start/stop functionality, right?

VAG CAMBELT REPLACEMENT INTERVAL CHANGE - General Automotive Chat - BRISKODA Lots of stuff about it all over the forum in the last 19 months or so. Good news for most folk who were binning perfectly good timing kits every 5 years, at their own expense, for no particular reason.

@J.R. I said in the reply above yours that it was a case of swapping in a working alternator, which I found on ebay for a very good price, genuine, supposedly from a 2010 vehicle with only 35k miles or something. Tested it by temporarily fitting it to my Polo on Friday. All fittings and connections were correct, shame I failed to notice that the pulley is offset outwards by about 10mm on a Polo one compared with this one! 😆 The belt rapidly derailed itself partially off the A/C pulley, but by the time I'd noticed that and hastily switched off, I'd confirmed that it was giving a healthy output. Belt appeared to have survived, luckily. The swap isn't a total piece of cake on the Roomy 1.2 TSI, 'cos there's no room to extract upward, and the A/C compressor has to be dropped down to get it out downward. Lots of oil all over the engine; source(s) to be confirmed and corrected. I will indeed start a thread in the Roomster Projects section, I think. Thanks for your interest. 🙂

I'm not exactly sure what my bet would be. Did you take any photos of the a-pillar wiring before you started the repair? Do the experiment with an added earth connection, data always helps. 🙂

The (brown) earth to the switchpack comes from pin 5 of the 32-way connector of the door module. It splits off to various bits of the door electrics from here (like the locking warning light), but does not appear to connect back into the main car loom via the connector at the A-pillar. So I guess the easiest thing to try is maybe take a wire from a known earth point on the vehicle, and join it to the brown wire that comes from the switchpack (pin 4 of the 10-way connector at switchpack). See if that fixes everything. If it does, you can maybe make a shorter link from the thick brown earth wire on pin 20 of the 20-way connector

Does the backlighting of the switch panel work when the vehicle lights are on? The switches and backlighting rely on the same earth wire for their operation, so checking the backlighting may demonstrate if the earth is compromised.

If you let me know the reg or VIN, I can check build date for you.

@J.R. I popped over yesterday with an A4 full of tools and a spare alternator. Charging happily now, but new battery ordered, looks like the 13-year old original in there, and was down at about 6V on arrival yesterday.

Thanks so much! Very smooth trip home thanks. Looking forward to working on it to get it all tip-top. (Probably for it to then be poached by my partner, who definitely likes the look of it. Guess I can always find another. 😁). Really enjoyed meeting you and your family.

Yes, that's a twin cam. This thread may be useful to you for checking the chain timing: Has my timing chain skipped? Any easy way to check? - Skoda Fabia Mk2 (2007-2014) - BRISKODA

Remove cabin fuse #7 and clean the contact surfaces. Then put it back in, noting if it feels loose. Then if the problem still happens, check the flat strip fuses in the fusebox above the battery. The power steering fuse is a 50 (or maybe 60?) Amp one with the thicker of the two red/black wires going to it. Examine the metal strip very carefully for cracks, photograph and post here if unsure. If you do find fuse 7 is dirty, corroded or loose, you should probably also find the fuse for your turn signals and look for similar corrosion, since that is also reported as an intermittent fault.

The only other part number that explicitly says for CBZA, CBZB engines without start/stop (which I assume matches your requirement) is 03F 903 023D, which is a 140A Bosch item. May be worth broadening your ebay/scrappie search to include that one.

I expect there's quite likely to be other versions including same or lower rated ones, perhaps a 110A Bosch that would fit. Will have a browse of the parts catalogue next time I'm upstairs near the 'big internet'.

The Bosch one can surely be refurbished, but it's not a quick and easy job, especially the first time you try. A few youtube vids exist, showing what's involved. I've done a couple, one including slipring change IIRC, back when I had bags of spare time. Doubt I'll do another. We seem to be on a bit of a parallel path. The one I tested on my Polo today was that same 03F...E part number, bought from ebay, but I need it to replace a broken one in a car I hope to buy tomorrow. Noticed that the back cover of these Valeo versions don't have screws or nuts holding them on, just plastic fingers that slide down threads, making disassembly more difficult. Parts catalogue actually says that the regulator/brushpack is a 'no replacement part available' from Skoda. Possibly because of these push-on fixings for the cover. Higher price for the reg may be just down to selling fewer due to this apparent 'harder to service' design.

Yep

Update 21/03/25 Audi going very nicely now, with the exception of a rattle that's almost certainly related to the one MOT advisory, front upper arm play, both sides. Nearly got a quote for getting this done, as it's all a bit 'heavy engineering' compared with what I'm used to. Fruitlessly changed a hydraulic engine mount on Wednesday, just in case it was that. Test drive filled me with joy for about 1 minute after that and then the rattle/clatter was there again, unchanged. 😆 Now there's a likelihood that both my Polo and the A4 will be going, in favour of a Roomster that I'm going to see tomorrow. It's like a blend of the two, in terms of size and shape (and mass). 😁 Petrol, turbo, blue, and something of a fixer-upper; why wouldn't I want that?

Most bolts that people think are, aren't. Angle tightening after a lower initial torque is simply a far more accurate way of tensioning fasteners than torque alone. Friction makes up so much of the torque 'resistance' that it results in highly variable fastener tension. Angle always results in same increase in tension, because the extension of the bolt is a fraction (e.g. 90/360) of the thread pitch.

Please message me if you still have the original motor @DJNafey , I may wish to give you some money for it.

No VW group part number to be seen? That number looks like just the brushpack/voltage regulator part.

Keying of connector looks right for both original Bosch and Valeo alts here. Perhaps that 140A alt really isn't 'drop in' compatible with your car, what part number does it have?

Might be room to hammer one or more of them looser for removal, depending on how crowded the engine bay is near the bolt heads.

Couldn't hold it all above open vice and take photo, but hopefully you get the 'drift'.

There's a trick with the lugs. The steel threaded bush is actually a tight but sliding fit within the inner alloy lugs. Before attempting to fit, you can move these outwards to increase the gap down the middle. Doesn't help with removal, but knowing it can make refitting much easier. Put bolt in several turns with it off the car, supported around a hole in something that the bush can move into (e.g. open vice jaws), then give the bolt head a few taps with heavy hammer. Only needs to move a mm to make a world of difference.

Strangely enough, I was planning to test a Valeo alt in my Polo at lunchtime, and I'm pretty sure the current one in there is a Bosch, so you may have saved me some headscratching if the connector doesn't fit.