What Year / engine type does it have?
Have they tried at least plugging it in to se if any stored fault codes are present?
Does it start up ok when cold or does it only stall when hot?
Have they checked it gets a spark or fuel?
X Regards ***** *****
No they have not tried plugging in. No earning lights cone on, it just stops and does not restart.
If we leave the car to totally cool down (approx 1 hour +) it starts first time.
New coil pack and ERG? Put on 6 months ago. They have checked the plugs.
On the odd occassion even if the warning lights dont come on doesnt mean you have not got any fault codes stored or pending even..its always best practice to at least plug in and check..so not sure why that wasnt done.... also as a when it does cut out ..checks need to be made regarding whether it still has spark..i say that because if it doesnt then it highly likely the crank speed sensor is at faulty.or going open circuit when it heats up.due the fault in itself...and of course once its cools then that circuit makes contact and re-establishes the circuit and the cars starts up only to go round the same problem again...another likely could be circuit issue within the ecu but that has to be really something thats need proper diagnoses before changing that or sending off for repair...if it was me id be looking into the crank speed sensor here..if its lost spark when it cuts out then that could be your issue..normally faults like these can be picked up through live data via the cars diagnostic port..so it maybe something for a garage to do and drive the car whislt its plugged in and record the live data and see if the faults picked up as and when the fault occurs or the car cuts out..that way they might have better insight in to what sensor is dropping out or going open circuit..I do hope this helps