mk2

I've just read the guide... as a refresher... why??? I 'must' be bored. Anyway, I think the culprit is the G40 sensor, or the plug or the cable/connection to it. I reckon the sensor is probably ok, but something happens when you crank it. Could be something shaking or loose? Could even be the crank sensor, but very unlikely.

It's described in one of these self study programmes... can't remember which one though. This is page 1: http://www.volkspage.net/technik/ssp/index2_eng.php late edit: it's on ...index3... near the bottom.

Hello. Pics please welcome to club Lupo!

Just an afterthought- is the adjustment system a closed control loop? What I mean is, for example; when the ECU dials in say 3 degrees of advance, does it measure how much the actuator has moved and then tweak it a bit to get it exactly right? Or is it open loop where it dials in the 3 degrees then expects it to be there without checking where it is? I may have just answered my own question judging by your error messages.... (it's closed loop).

Ideally, you need to see what the ECU is seeing on a car without a problem, and then compare their results with your's. The tell tale to me is that once you've cleared any faults after it's been started, the ECU isn't trying to move the cam. Now, is that normal, or is it normal for it to move it? I don't know. So, if the ECU usually moves the cam (without clearing the faults after starting) perhaps it moves it too far (or not enough)? Why? But, if it doesn't usually move the cam, why is it moving it? Anyone reading this must think this is complete gibberish 🙄 I still have a hunch that somewhere the timing is out; the ECU is picking up the discrepancy and trying to correct it. Or a sensor is in the wrong fitting position, making it look like the timing is out. I don't think it's a wiring fault. I also don't think it's a mechanical fault.

Ooh, that pic does it for me... i wish mine looked that good. Mmmm.

Any tricks to clean the insides? Looks good BTW.

I'm convinced that Lupos are going the way of Mk2 golfs... Ever more desirable as they become rarer and rarer. Even in breakers' yards Lupos are a rare sight now. Be nice to see one of the first Lupos in the UK go to a good home again. My fav colour too.

No easy way... You may need to pull out the blower motor and get in there with a vacuum cleaner. You could have a look if you can see anything via the pollen filter holder (removed first). If the bits are downwind of the heater matrix and are already in the ducts, you might be able to blow them back down into the foot vents and then out with the blower motor. Careful use of the air direction control will help Try a cold hair dryer first. Then compressed air if no luck.

Yeah, I'll second @Rich. I'd only do the pedalbox if the clutch is creaking or is visibly lower in the rest position than the brake pedal. I would do a gearbox oil flush. And any loose gear linkages. And perhaps the gearbox selector shaft seal.

I don't think that it's a wiring fault. The fault doesn't show up till after the engine has been started. The ECU runs through a very thorough check of plausable sensor values, bus currents and open circuit type scenarios before moving on to normal running. If there were a wiring or sensor fault, it'd flag before the engine was started. I have a gut feeling that it is timing related. But what exactly is slightly out, is the question... I wonder if a timing sensor is picking up interference from somewhere (really, a stab in the dark now!). Tried disconnecting the alternator? Dodgy (electrically noisy) fuel pump?

Yeah I tried to find the part number for you. Looks like they don't come separately. Might be an ebay jobbie or chance it down ECP or GSF? I think it's M12 but you'll need to check. https://www.ebay.co.uk/itm/261863096082

I think the banjo, copper washers and hose come complete...? https://volkswagen.7zap.com/en/rdw/lupo++lupo+3l+tdi/lu/2002-231/6/611-611020/

Good point 👍🏻

Just had a mad idea, but might be going well off track... I've never done a cam belt change on that specific engine. But i have on others with cam actuators. When I change the belt, I make sure to reset the actuator, so it's in the stop position. Way out there, but is it possible that when the timing is checked, static, the actuator isn't at rest? As in, timing might be out, but looks ok because the pulley has rotated to compensate... Just thinking of when fitting dizzys on old engines which make the bevel gear shaft position pot luck- often they're out too. But I think I'm wrong- there's a setting tool usually used when doing a belt change on your lump. Only thinking out loud. @Rich may have an idea.