Clipper Cabrio running problems

Hi all
My wife's 89 1.8 Clipper Cabrio used to idle from cold at 2000+ rpm, even on warm days, then die down, but run a bit lumpy.
Then a few weeks back, the centre section of the exhaust split from the backbox, but she continued to drive the car. After a week of driving it, the car started stalling during driving. We've had the exhaust changed, and it's still dying all the time. The car will start fine, then run for a while (1-2 mins) then dies, even with the accelerator down fully. After leaving it for a minute or 2, it'll start again, and die again after 1-2 mins.
We took it to a mechanic who gave us the usual 'Swap the Pierburg for a Weber', but she'd like to keep to Pierburg carbs. I'm worried that if we change the carb, the problem may still be there. I had the same problems with my Scirocco (was told to swap to weber, spent £300, and found it was the rubber carb mount at fault).
Apparently the mechanic checked for leaks, but found nothing. I'm going to try blowing compressed air into the carb jets tomorrow, to see if they're clogged up.
Do you think a carb change will fix this, or is it something else, like the inlet manifold o-ring?
I'd appreciate any help, as a carb change will be expensive.

Thanks
Phil

sounds like a fuel starvation problem to me have you tried looking if the fuel pump is running at the right pressure even the mechanical ones can slow down with out stopping    

There is a brilliant guide on the pierburg Carb by Rubjohnny it's under the engine section I believe, just use the search facility.
I had a problem with mine and all I needed to do was to clean the airfilter housing and put in a new filter and Sprayed carb cleaner into the carb to flush any muck out. On the clipper you need an in line fuel filter to keep muck out of the carb, you can get rust from the filler neck so  a replacement and a tank clean may be needed also, but try the carb cleaner first.

I'm gonna try cleaning the carb jets with spray, see if theyre clogged.
I've got a working fuel pump from my Scirocco, same engine. Thinking I might stick that on, see if it changes anything
A carb replacement is totally last option ATM, I spent loads getting the Weber put on mine.

the thing thats making me think its not the fuel pump is that it's idling ok. I can start it u, and it'll idle. It seems to die while on the move.

Two things spring to mind with the symptoms of starting OK then dying but then starting OK again if left for while;

In the recent cold and damp weather the carb is icing up, freezing water vapour, when left the ice melts and the car starts and the cycle is repeated. Check all the warm air manifold plates, hose and vacuum pipes are intact and working.

Water and debris has got in to the fuel tank via a corroded filer pipe. The crud is drawn down the fuel lines and causes a blockage. Check the fuel filler pipe and inside the tank via the inspection plates/level sender.

Having said that the E2E is the devils own work when it plays up.

I went out to the car to spray round for leaks, no change.
I did notice that inside the inline fuel filter, there isn't a lot of fuel coming through, its a trickle rather than a pour (comparing it to my Scirocco).
The fuel that is coming through is frothy, full of air. It's white and really bubbly. The car will run for 2ish minutes, then the revs drop (even on idle) and the engine dies. After 30 secs, it starts up again.
Could this be muck on the fuel pick-up? Dodgy fuel pump? There's no sign of fuel on the floor under the car.