Got under it earlyer and have noticed the 2nd 02 sensor is not fitted
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this may be the route of it !?! Think if it was the way it is due to mods it would be like it all the time , also seems excessive so can't imagine any tuner would let a car go out like this , and if im honest i dont remember it being like it on the test drive and first day or so of owning it .
I did the oil swap to the recommended nanno drive , changed the plugs earlier and noticed i have oil leak onto one of the spark plug wells from the rocker cover gasket , so these will be my first fixes