It becomes thicker.
As the temperature goes up the oil pressure goes down because the oil thins out. It is possible that the increasing temperature which causes the 'temp' light to come on can thin the oil enough to cause the 'oil' light to come on also.
Heat reduces the viscosity. 5w-20 is 5 when cold-20 when hot. Lower no. is thicker.
Engine oil will not freeze at any temperature you will encounter. The freezing point is not fixed and depends on many factors. Oil will however get thicker as the temp goes down.
Yes, it may make oil sink if at some temperature the density of water goes lesser than that of oil.
my oil pressure goes up while I'm driving and back down when I stop what could cause that
It locks up the engine and ruins it
Goes up and down if there are more particulates of oil
On the automatic it goes down the dipstick tube.On the automatic it goes down the dipstick tube.
There are many reasons why NYMEX crude oil goes up and down in prices. This includes the level of production from crude oil suppliers as well as world events and government policy.
Check oil level, oil filter, oil pump.
Worn oil pump or worn engine bearings.
It is normal for the oil pressure to drop some when warmed up.