Yep, or something breaking down when hot. Crank sensors, coils and ignition modules can all do this
"No the temperature gauge doesn't work........
we've driven 150 miles today........
the heater went cold last Thursday........
they check the level when it's serviced don't they?"
Reproduce the fault, check spark. If it has spark then look at the cts and wiring which often had insulation failure inside the black plastic tubing it is in. If the eml doesn't go out on cranking at all then look towards the crank sensor. No spark could mean coil or amp but equally the crank sensor that's why it's good to look at the eml on cranking.
"No the temperature gauge doesn't work........
we've driven 150 miles today........
the heater went cold last Thursday........
they check the level when it's serviced don't they?"
Have you had a chance to reproduce the fault and check for spark when it won't run? If it has no spark then you are more than likely left at coil or amp. If it does have spark then fuel pump or relay, relay being the more likely of the two
"No the temperature gauge doesn't work........
we've driven 150 miles today........
the heater went cold last Thursday........
they check the level when it's serviced don't they?"
gsi pie wrote:coil n amp changed along with fuel relay
still got the problem
been told "could be head gasket?? strange I know thought id ask
How strange, someone used to modern cars that have overheat protection perhaps. You have covered the common stuff now, so you are going to need to narrow it down a bit by checking what you do and don't have when the fault occurs. Fuel and/or sparks. Given that you have changed the dizzy, coil, amp and effectively the entire ignition it is probably safe to assume that the problem is going to be fuel side, but check it anyway. The only other thing that could affect the ignition is the ecu. Fuel wise, did you inspect the wiring for the cts as suggested? Jury rig a bulb on the fuel pump feed so you can instantly see if it loses its supply? There's not much left really that fits the symptoms but if you can follow the diagnosis process to determine what you do and don't have, rather than randomly changing bits, then it will help to pin down the cause. You get the odd ones occasionally that defy logic and the cause doesn't fit the symptoms properly.
"No the temperature gauge doesn't work........
we've driven 150 miles today........
the heater went cold last Thursday........
they check the level when it's serviced don't they?"
Definitely fuel supply then. Damper, as Gaz suggests is possible, though I have never heard of one causing these symptoms myself. Other ideas, obviously pump, vacuum in the tank due to blocked breather? crap in tank blocking the pickup? You swapped the relay didn't you? Volt drop at the pump?
"No the temperature gauge doesn't work........
we've driven 150 miles today........
the heater went cold last Thursday........
they check the level when it's serviced don't they?"
Take the fuel filler cap off pie, if you have tank breathing issues it can lead to a vacuum in the tank that the pump struggles to overcome. Removal of the cap prevents the vacuum build up helping to diagnose if this is what's going on.
"No the temperature gauge doesn't work........
we've driven 150 miles today........
the heater went cold last Thursday........
they check the level when it's serviced don't they?"
If the voltage remains fine at the pump right up until it cuts out then the relay is fine. If it's fine standing still and only cuts out after time actually driving then my money would be on something floating in the tank and clogging the pickup. I had a similar thing on my capri, and have had a couple of older cars with the same issues roadside too. You could rig an alternative feed to the pump with a can of fuel and a long piece of fuel hose to confirm. Otherwise the pump itself sounds likely. My capri would drive between 8 and ten miles then lose fuel pressure following each clean out of the tank, but once the problem returned it would idle all day long but as soon as I moved the car it would die. I never did find the cause, I replaced the tank and pump when I got fed up with flushing the tank. The ones I have had roadside have been old cars with mechanical pumps on the engine, so no roller vanes and I have blown back down the lines to dislodge the offending item.
"No the temperature gauge doesn't work........
we've driven 150 miles today........
the heater went cold last Thursday........
they check the level when it's serviced don't they?"
then gets worse and cuts out
only when warm
strange I know thought id ask 
