I have an '05 Ram 1500 with the 5.7 l Hemi. The truck has 120k on the odo. Recently I noticed that when I start the engine, the oil pressure gauge doesn't come up, and the warning light comes on. However, if I immediately shut it off and re-start, the gauge comes up and the warning light is off. Then the gauge is up and stays up in the normal range. There are no clattering noises while the engine is running, so I believe the engine is getting oil. When I first noticed this, it would happen sporadically, but now it happens almost all the time. It doesn't matter if its a cold start or the engine is up to operating temp. If I've been driving and stop and get out, when I get back in and start up, it does it. The truck doesn't leak or burn oil. I do my own oil changes and check the dipstick regularly between changes, and the level is always where it should be. I'm pretty sure the pump is pumping oil, so I'm thinking its the sending unit, the gauge, or the connection between the two. Has anyone else come across this problem, and am I looking in the right direction?