1991 H REG MK1 GOLF GTI CABRIOLET WONT START WHEN IT GETS WARM

MY 1991 MK1 GOLF 1.8 GTI CABRIOLET WILL NOT START WHEN ITS WARM ,IT RUNS PERFECT VERY SMOOTH EVEN WHEN RED HOT BUT WILL NOT RESTART ,IVE NOTICED THAT IF YOU PULL THE BLUE CLIP OF THE 5TH COLD START INJECTOR IT WILL RESTART ,IVE REPLACED THE  ACCUMALATOR WHICH HAS DONE NOTHING ANY HELP ON THIS MATTER ,IT MAY BE THE COLD START IS STAYING ON MAKING IT TO RICH I DONT KNOW A AWFULL LOT ABOUT THIS PROBLEM

a 1991 with CIS?

K-jet fuel injection or digifant fuel injection system?

If K-jet leave the 5th injector unpluged… I ran for about 3 years with no 5th injector as I had leaking injectors but I had a problem with lumpy running when cold as to much petrol.

When the engine is hot the 5th injector should not fire, it's controlled by the thermo switch in the flange on the front of head, there is guide in the Haynes manual on testing the switch and 5th injector. Again all k-jet info as I've not "played" much with digifant.

P.S… THERES NO NEED TO SHOUT.  

I've just been through 10 years of hot start issues!! 

Get the fuel pump checked to make sure it's holding pressure and check the warm up regulator. Get the whole system pressure checked professionally.

if it starts with 5th injector unplugged then either the thermoswitch is dead, the green/white wire from 5th inj to thermoswitch is shorted to ground somewhere, or you have leaky injectors dripping fuel into the cylinders