87 560 sl Intermitanty dies

[bergmjh]

I have an 87 560 sl that is giving me problems. Intermitantly mostly on warm days it dies and will not restart. 10 minutes later it will restart. I is in the shop and the mechanic has replaced the crank angle sensor without any help. They have narrowed down the problem to the fuel system. The fuel pumps shut off when the car dies and there is spark when the car will not restart. How does the fuel pump relay work in this car? I am wondering if I am losing the power to the relay or if the relay is the problem. Any help would be apreciated. Thanks John