When initially starting my Ram 1500, the oil gauge does not work, if I stop the engine and restart, it works.?

When I initially start the engine, the oil pressure gauge does not work and the ';check gauges'; light comes on. If I immediately stop the engine and restart it, the oil pressure gauge starts working. This works every time. Is this a faulty gauge or faulty oil pump? 2004 Ram 1500 model.When initially starting my Ram 1500, the oil gauge does not work, if I stop the engine and restart, it works.?
you may want to check out the ignition switch on it also when they start to go bad they will cause this too happen,that wouldn't be the oil pump unless the high pressure release valve in it was sticking open causing a lack of oil pressure,and that rarely happens,but its possible and so is the possibility if the sending unit being bad also,or a bad ground or loose wire,i have only seen one oil pump do this and that was on an older model dodge with a lot of miles on it,good luck.When initially starting my Ram 1500, the oil gauge does not work, if I stop the engine and restart, it works.?
shouldn't be the pump, they are engine driven and positive displacement they should work all the time or not at all, but for added insurance take it to a garage, or get a manual oil pressure gauge just to make sure.