Oil Pressure issues
My Tahoe 5.7L engine shows good oil pressure at start up, after driving a little while the pressure will drop to zero when I stop - but will increase steadily as I accelerate. But as I continue my travels the oil gauge will work correctly and show (approx) 35 psi when I come to a stop?? Took it to a dealer and he said I had 6 psi at idle - I am curious as to why the gauge will work properly from time to time? If this is an actual oil pressure issue, can I intermittently have good & bad oil pressure? The truck was in storage for a year and a half and has 136,000 miles on it, I do not know the history as I purchased it at an auction. Also I drove over the Railroad tracks once (very bumpy) and the oil pressure gauge dropped??