Electrical problems... still !

well after winter the mechanic that put the new engine in my jeep finally pulled it back into the garage to have another go at getting it running. When turning the key to the "crank " position it wont start. Sometimes when the key is left go to the "run" position it will start.. when it does it idles fine but any gas its cutting right out.... any help would be greatly apreciated!!

thanks again

keith

does anyone have a schematic for 01's ?