HELP (running problem_

I just got this escort as a commuter car and it has been running good, until about a week ago. In the morning when i start it to go to work it runs great, in the afternoon or at lunch when i start it it idels rough and has no power to even get out of the parking space. If i shut it of and on a few time it will start running fine and i can get home. Took it to the dealership and they don't have a clue and they want to tear into the lower part of the engine. but it sounds to me like some short or possible sensor, since it runs good some of the time. Please help so I am not lead in the wrong direction by for and spend more money then the car is worth.

93 escort
1.9L
Automatic

have the coil tested.. sometiems the internal components of it will degrade and wil caus just what you described when warmed up or cool or damp.etc it varies.. but it shouldnt be anything as a extreme as the lower section of the engine. most likly electrical.