Re: 155 injector light Heebie jeebies!
Doesnt sound like it.
I have experience of failed cam phase sensors (behind exhaust cam pulley)on two twinsparks both 2.0L cars.
In neither case did it affect the idle of the car.
In neither case was the injector light on permanently.
However as the cam phase changes, via the variator, the ecu has no way of knowing. For day to day running this didn't cause any issues except that the car felt a bit held back when accelerating between 2 to 3k rpm.
BUT every now and then at low revs when accelerating the car would suddenly lose all power for a brief second and then injector light would come on for about 5 secs. The only way of describing it is like the ECU resets the map (to use only the crank sensor) and restarts.
If you unplug the phase sensor then the ECU will ignore it and use the crank RPM sensor instead. You can test this and afaik it should not affect the idle. If you're problem is still the same with it plugged out then its not the cam phase sensor.