Hi,

After having changed my oil (Castrol Lightech 10W-40 - samme as I always
use) and oil-filter, the oil pressure act very different from what I'm used
to.
I've always had a very good feeling about the pressure, eg. how long it
takes to get stabil in idle, how high it is at different rpm's.
Now it takes much longer time for the pressure to get stabil in idle (just
below 2 kg/cm2).
I've always used the pressure as an indicator to when the engine is fully
warmed up, and now it seems to take at least twice as long.
When I first drove it after the oil-change, the water temp was extremely
slow to get to the normal position, but now is rises normally. Still, I have
a feeling, that the engine takes longer to get warm (using the pressure as
indicator).

Can anyone explain what has happend? Should I just ignore it?
The car is a Miata 1,6L from 1990.

Regards,
Thomas, Denmark.