I just noticed the oil pressure gauge on this Pontiac TS GT stays in the red zone at idle and climbs a little out of it at 2000 rpm and higher (never over the first unit).
There's no other warning light or error in the dashboard - just the scary oil pressure gauge.
We brought this car home for repairs after a 600 km trip (370 miles) without any issues in mountain roads or hot weather. Engine temperature was well below the first quarter mark, acceleration was great and there was no strange sounds whatsoever...
When first started cold engine has no lifter or tapping noise.
Do you have an idea what would be the most obvious sign of oil starvation/low pressure on this engine?
Is there any way to confirm it beside the dash gauge?
From your experience with this 3.8 engine what would be the most probable cause for this:
1. defective oil pressure sensor
2. failed oil pump
3. worn crankshaft bearings
4. worn camshaft bearings or other cause