papermushrooms

Hey guys im having some serious issues getting this fixed, car has been in the shop for 3 days now and is costing me a fortune trying to get this **** sorted so any input would be greatly appreciated, i had the engine check light come on so had the ecu scanned and its come up with P0343 cam position sensor, i've had the sensor replaced with genuine parts and its still coming up with the fault straight away after it is cleared, the tach still works fine and the sensor plug has been checked and so has the wiring from the plug back to the ecu, the correct voltage is getting to the cam position sensor but its just not picking anything up, the motor has been stripped down and the cam removed to check damage to the ring gear at the back, also had the timing set shimmed and checked, all the lifters are aligned on the cam lobes, and at this point the mechanic has no idea where to go to next other than try a different ecu? thanks in advance