Hi everybody. New to the site and wondering if anyone has any input. I have a 1988 100CD Avant wagon (second owner and had it since 2012, first owner was a Volkswagen dealer principal). It is in amazingly original and excellent condition (every panel still wears the original factory-applied paint). Recently, it became difficult to start (it will start after six to eight attempts, and then runs perfectly). I suspect it's an issue with the cold start valve which the workshop manual suggests "is not a user repairable item" and, of course, new replacements are not available. It's in with my repairer (a Euro specialist) but I haven't heard from him for a week, so it doesn't bode well. The car is way too good to despatch, especially for such a comparatively minor problem, so I'm hoping someone can give me suggestions. I've attached a couple of photos of the car, FYI. 

Hello Paul,

I too would suspect the cold start sensor - valve? - not sure about the valve set up. 
Availability? - take it you’ve checked EBay. 
Kind regards,

Gareth. 

Have you considered the injectors or glow plugs? 

On my A6 c5 I've had to change the glow plugs. But I think I'll have to change the injectors at some point. 

Hi all. I discovered a connector disengaged from the fuel metering device. When I reconnected it, the car started (hooray!) and after one initial drop in revs, idled perfectly. I repeated the procedure three times from a cold start with the same result. Looks like we're back on the road. Still doesn't explain why the car would eventually start and then run, but I'm not looking a gift horse in the mouth. Thank you all for your advice and input.

Many thanks Paul,

I’ve witnessed such disconnections with your era of vehicles when they have become flooded with fuel and won’t start. Anyway, all is now well.

Kind regards,

Gareth. 

1 hour ago, murrellp said:

Hi all. I discovered a connector disengaged from the fuel metering device. When I reconnected it, the car started (hooray!) and after one initial drop in revs, idled perfectly. I repeated the procedure three times from a cold start with the same result. Looks like we're back on the road. Still doesn't explain why the car would eventually start and then run, but I'm not looking a gift horse in the mouth. Thank you all for your advice and input.

Glad we could help 🙂