.Hi, it is leaking through the oil pressure sending unit, when cold pressure is high due to thickness of the oil.
replacement of oil pressure switch is a must.
Since it doesn't lose oil after a few minutes warming, can I get by not changing the switch for a couple thousand km? I live a long way way way from my mechanic. How difficult is it to change?
it is not dificult or expencive, switch like this is only 5-10 dollars, just unscrew and screw in the new one, any automotive supply shop can get you one, and yes you can drive with it, I have seen many leaking, but never seen one to burst open.
Any suggestions on how I can improve the power from this engine. I've heard that little things like a different exhaust system and breather/air filter can help.
I am not expert in performance modifications,you can try K&N filters. if you really want to boost it though, you can look at instaling performance camshaft and larger intake valves.. Go to toyota performance site.???