This is a B4204S (2L petrol) engine on 99 Volvo S40. Timing belt got snapped when driving. And I had to do total engine head make over with new valves and stuff. Too expensive. However the repaired head isn't installed yet. Since there's a fault code P0340 (Cam shaft position sensor error), I'm afraid whether the belt got snapped due to the bad sensor. Any opinions?
Another two suspensions are
1) Timing belt was too-old (Engine on 152000km, I got the car by 140k but failed to replace t belt)
2) There was some oil leak from camshaft oil seals. Oil weakened the belt maybe.

 

So you haven't put the head on yet, right?

If so, the code was set because the belt snapped. It didn't cause the belt to snap.

 

No I haven't put, because head comes from the repair shop this Monday. It caused me an arm and a leg to fixed it. It was too late when I found out that whole head was too cheaper than repairing it.
Thanks a lot for replying. Good to know that the cps doesn't do any trouble. Because I was desperate about the fault code. Thanks again