Update

Next morning - Saturday - open bonnet, pull off engine cover, remove section of inlet manifold that prevented straight access to the front left glow plug - on my right as I'm looking at it - try tightening - just turns uselessly - try loosening - turns uselessly - try tapping glow plug down a bit to see if that will engage a thread - try levering glow plug up while unscrewing it - no, I'm still screwed. Neighbour comes out with a knowledgeable mate of his and they work out what's wrong.

The thread of the glow plug is still stuck in its tapped little hole. I have sheared the nut section so that it just wiggles and turns which ever way you try to turn it with no effect on the threaded part.

To me this is good news as there should be no loss of compression and the engine should easily start on five of six cylinders.

WD40, Pulling, drilling and wrenching follows to see if this might release this recalcitrant plug. All that happens is the tip contact comes off, shortly followed by the hexagon part of the shank that had sheared through.

The remains of the glow plug are firmly stuck and after sawing through one of the old glow plugs, I reassure myself that no material has fallen off inside the engine and none will do so.

On reinstalling the piece of inlet manifold I notice that only the top half of a gasket had been in place for the pipe connecting to the turbo. Clean metal under the gasket covered half but ingrained coked soot on the half where the gasket was missing. This on a car that has supposedly only been handled by Audi technicians.

Clean the surfaces, lightly coat with gasket paste, reassemble, have two mugs of tea.

I start the engine - certainly quicker starting than before thank God - more importantly it runs smoothly and quietly, well for me it sounded less wheezy, which was probably the turbo waste gate leaking.

Test drive - things are OK - phone call from local A and E please collect your wife and daughter. Perfect timing, and not unusual due to wife's untreatable neurological problem.

Pop down to A and E, usual wait for Dr to come back after consulting their senior, impressed as none of the usual ' are you taking your medication deary' and get them all back in the now functioning car!

Garage bloke turns up on time in the evening - and this is a Bank Holiday weekend I believe - doesn't charge for the call out and gives helpful advice. Drill out more the core, run the car until engine hot then use an easy out to try shifting remains of the glow plug. I decide to leave things as they are for the time being.