XSeries-forum

Hi everyone. Can someone confirm symptoms of cam sensor failure please? I've noticed a dropping off of low down throttle response and a reluctance to start especially when warm. 2-3 seconds cranking when cold and occasionally taking a good 8-10 seconds cranking when hot before firing up. Initial thoughts were fuel filter issue, but just had a service last week and it's still doing it.
Checked online, as you do and cam sensor seems favourite. I've checked voltage across terminals 1 & 3 which should be getting 5V but actually appears to be very close to 12V according to my somewhat ancient multimeter. I can't check resistance due to same ancient multimeter malfunction. So it was a rather ineffectual test ::)
Hopefully getting my nephew over with his box of tricks later to pull any codes. Does the cam sensor throw up a code even? 
Finally any mileage in those cheap senders on fleabay or should I go genuine BMW?
TIA.

Also the same symptoms as leaking injectors , use the search button and search leaking injectors.
As for the cam sensor, no idea, sorry

*UPDATE*
I'll try to give as much information as possible.
Symptoms are as follows.
Cold start cranking 1-2 seconds ish.
Hot start cranking usually 3-4 seconds, very ocasionaly 8-10
Throttle response sluggish at low revs fairly unresponsive at higher speeds.
OK when kicking down.
no white smoke from starting either hot or cold.
Fuel pump from tank appears to be operating normally.
Tested for error codes and got 09f6 (Rail pressure monitoring on engine start)
1e30 Boost Pressure Control.
Also 3505 Glow plug system. (Had this since October. Never a problem starting from cold initially) 
Cleared codes and started engine cold. (2 second crank) No codes shown apart from glow plugs..
Drove car and warmed engine up and restarted it when good and hot. (4 second crank) Got the 09f6 code again. along with glow plugs but not the boost control.
Checked rail pressure and got what you can see in the image.
Can anyone shed any light? Clues? Other possible causes than the HP fuel pump?

Exactly the same as my car when i first got it.
I thought it was the cam sensor but no change after fitting a new one.
Asked on here but didn't like the answer but they where spot on.
2 new injectors later and it starts perfectly hot or cold.

Thanks guys. I'm going to try the following. Does this make sense?
Clean the in tank filter because apparently the low pressure fuel pump should be pushing 4 Bar.
Perform a leak off test and see what that shows up.
And then I'll take it from there.

Perform a leak off test first.

I had a similar issue a while back and it turned out to be two injectors. Went through the same as you with fuel pressure sensor and and cam sensor to no avail. Also replaced LP fuel pump. Local garage did a leak test and refurbed all injectors.