V6 2,5 Really hard to start

[Benjaminsson]

Connie V6 2.5 1999 -Living in Sweden far away from a garage with a T4.
I have a problem. Has now got together my engine after the timing belt tensioner broke. (24 valves replaced) but the engine is hard to start. It takes about 15 seconds of cranking before it starts. (Sometimes I have to repeat it twice) Then it goes excellent. When I connect ODB2 to the computer, it displays the error P0340 Camshaft sensor circuit Malfunction. I've switched to a new sensor, checked all the cables, relays and contacts. When I measure the voltage, it will show yellow / green -12.5 V, blue - 4,99V. Seems ok according to the information I found here, but the problem persists and P0340 comes back. And back, and...
Now I have run out of ideas and asks if anyone on this forum can help me?

I am after all the bad luck I had with this car, still very fond of the car but I can not run it and be worried that it will not start.

I forgot to mention, The ECU is dry (never been drown) and looks fine to me but I still suspect there could be something there. Does anybody have a wiring diagram or measuring values for it?