hi i replaced the maf sensor on my audi. It now judders at idle with the revs fluctuatting by them selves if i unplug the sensor enginr ticks over smooth also when i switch the engine off i get the light symbol and the break warning light followed by the low oil presure light and a beeeeep. If i put the old one back in it all goes back to normal no problems. I have looked around but cant find anyone with all those errors just from changing the maf sensor. Thank you f you can help. On a side note which vag com cable do i need for a audi a4 140 2lt tdi B7 2007 convertible and is 39mpg uk miles normal for motorway driving.
