A vacuum leak could do that. If the check engine light is or has been on, have the vehicle scanned for codes.
Need to know the year and make, It would help answer.
It's lean.
Perhaps you need to try a higher octane fuel i.e. 89
9 to 19 PSI. / LBS. NO lower are higher are you will have problems.
Probably worn bearings and a tired oil pump.
It could be low on water and stuff, fill it.
This is normal. It will decrease at idle conditions and when it is at normal operating temp. Higher rpm means more oil that needs to be pumped through the engine to keep it lubed up.
White smoke is from burning radiator fluent.
lack of lubrication
It's lean.
It all depends on the rating of your thermostat which is usually 180 to 195 degrees if using a aftermarket temperature gauge and headers the temp. gauge reading will be higher than normal because of the excessive heat from the headers.
195 to 210 degrees is NORMAL operating temperature.