OT Dash question - Explorer & Exp. Sport Trac

Dash guage question for anyone who has one -

Just got a cherry 2001 Explorer Sport Track with trailer package, and I have noticed the oil pressure gauge does not always work when cold. After a few seconds, it "zings" into action, and does not do it again unless the truck sits overnight, and then only on occasion.

Has anyone had similar experiences?

I love the truck, finally room for the kids!

Many Thanks!

I looked at three different E.S.T's, and they all did the same thing. One rough truck also had the temp guage not work, but it turned out to be a stuck thermostst, and I stayed far away from that one!