hello everyone got a prob with my obd2 aaa vr. started to run really rough after cleaning under the bonnet. wont idle properly smokes badly but black not blue, does about 5 mpg. had it tested on a diagnostic machine and it threw up faulty earths on air mass meter, lambda sensor, idle stabilisation valve and summit else i cant remember. does anyone know which earths to clean and where they are situated as its doing my head in have already cleaned up the ones on the neg terminal and the six that run underneath the battery tray but now am at a loss as to where to go next