Honda CRX esi engine problem
 

Hi I have bought a Keg Honda CRX (mk3). Sometimes when it's ticking over your can hear the engine tone going up and down rythmically. Also, at high revs and under pressure it kicks out what looks like white steam with a hint of blue. It seems to be burning more oil as well and the spark plug threads have dirty oil on them even though it's recently had a oil change. Other than that it seems to run fine and the engine tone is smooth most of the time.

Anyone got any ideas?