engine switching off/stalling after 10 mins of driving

Hi everyone,
I drive a 2.0 ford focus '02 zetec.*
whilst driving at speeds between 40-60 and stationary, my car's engine will completely shut off within about 10 mins of driving. after this happens, the engine will crank but won't start. only after 30 mins or so will the engine start again at which point I can drive another 10 mins before the engine switches itself off again. this happens everytime I drive it.*

I took it to my ford dealer, who promptly said it was a problem with an electronic part of the fuel pump overheating and malfunctioning, causing the gas to be cut off.*

I've talked to another mechanic who says that the fuel pump would not make the engine turn itself off, and that I should get the dealer to run a computer test of the sensors or something rather. I wasn't too sure what he was telling me.*

my question is, what should I do? I've left the car with te dealer overnight who are already going to charge me for the quote. should I get them to get this electronic sensor report or whatever? and if I do, what test do I ask for specifically? has anyone else had this problem?

thanks so much for any help in advance, this is really doing my head in and I'd really just like this whole issue sorted.*

For the diagnostic fee, they will already charge you, I do not see any reason why they can not check every sensor that could possibly be involved. You took the car in there to have it diagnosed and you should not pay the diagnostic fee until the service is completed. Being a Ford dealer they should have every piece of available technology to find the issue! It may just be me but if I was paying to have them find the problem I would not pay them a dime until they do so!