Oil pressure & white smoke

[jcline]

When idling at normal operating temps, the oil pressure guage reads, barely above the line on the very left side. But when zooming around town and stuff, it's usually normal, if not a little bit less. But how would we go about fixing or, telling what the problem is?

Also, once in a while, the car smokes big time, white smoke. Like today, we had the car idling for like an hour. And we went to 7/11 and it was smoking like crazy. We changed the oil, and clumps or something came out. So we put the new oil in. and it still smokes a bit. But once we got on the highway and back to vancouver, it wasnt smoking. We Would really like to know whats going on.