bmw z4 misfiring issues

[jamielouisewright]

Hello I have a 2006 bmw z4 the problem started with the car revving itself when idle. I took it to my usual garage who put it on the computer and it came up with the fault code for engine valve tronic server. He advised us to take it to a BMW specialist which we did. They have changed the part, we collected it but there was still the initial problem but the car was now miss-firing as well. the garage put it back on the computer and it said cylinder 4 was miss-firing, The BMW garage advised us to have a full service and to put a new coil pack on c 4 and new plugs which we did. We collected the car again from the garage but once again we never left the garage as now the car is miss-firing. It went back on the computer and came up with miss-firing on 3 and 4 cylinders, the BMW specialist isn't sure what is wrong now. has anyone had similar or the same problems as any advice would help. thank you

 

[ph001]

I'm assuming it's a 2.0l? Be nice to have the numbers for those codes. If they have changed the valvetronic motor unnecessarily I'd be pretty upset as it's an expensive part. Saying that, idle issues on the 2.0l do involve that part quite commonly as well as the eccentric cam sensor - this is the sensor that validates the valvetronic motor position so the two faults can easily be confused.

It would seem a big coincidence that the misfire suddenly appeared at the same time they have swapped bits so I'd strongly suspect it's something they have done.