KEEPS STAILING!

Hello people,

Quick question, Got an 82 MK1 1.6 GTI, had it since September and all is going well but I have 1 small problem and could do with some expert advice.

Car runs fine and performs well but occasionally it fails to start first time. If I turn the key it will fire up and then stall within about 2 seconds. If I then try and start it again it just turns over for about 20 seconds and eventually fires up again but runs badly and misses, (as if its struggling for fuel) if I rev it if slowly comes to and runs fine. This happens usually after I have been driving it earlier the same day. Any ideas, Local mechanic is a bit stumped, he suggested possible accumulator / fuel pressure issue? Any advice would be much appreciated as this small problem is becoming an annoyance and spoiling my overall enjoyment of the car,  Usually happens at the worst possible moment. (When some one is watching ) , HA HA HA

Do an injector test for leaky injectors and put a fuel pressure guage on it to check in particular control pressure and leak down of residual pressure