Hello, I have a 2000 volvo v40 1.9T. When I start it in the morning it starts fine and idles around 900-1000 rpm. Once it is warm the idle will drop to about 500 rpm. Then when I shut off the car and try to start it back it will sometimes start and idle rough around 500 but sometimes it will start then immediately die like its not getting enough gas. It gives me two codes. When I clear the codes and drive it the first one to come on is P0341 camshaft position sensor and then when I turn the car off and try to restart it and it dies the code P0335 crankshaft position sensor comes on. Should I maybe start by replacing the camshaft sensor since it comes on first? The sensors are not cheap. Is there a way to test the sensors first to make sure that they are bad? Any help would be greatly appreciated. Thanks for your time.