Land Rover Repair: Idle speed Land Rover Discovery 1, land rover discovery, fuel pressure regulator

Question
Hi Nigel,
My 99 Disco, with 199000 clicks, just came from the shop(not a Land Rover specialist) from a head gasket change. (Had no choice)
The first thing that I noticed is that the idle speed was around idle.
First question: How do I lower the idle speed?

I drove de car to Logan Airport and on the way back the car stalled, as if it was missing gas. Limped back to the mechanic and they first said that it was the fuel pump because the fuel pressure was a little low, but after, the story shifted to a defective crank or / and cam shaft sensor.
I pick-up the car and drove it home. Drove fine, the only thing is the abnormal idle speed.

Should I change the fuel filter?
Should I change the fuel pump?
Should I change the crankshaft sensor? The car starts fine.
Should I change the cam shaft sensor?
The check-engine light is yellow due to faulty air sensor.
Let me know your thoughts
Regards,
B.Goldstucker  

Answer
Have the base idle reset and check that the vaccum line from the inlet manifold to the fuel pressure regulator is good. It sounds like this will probably resolve your problem.  Otherwise, cam sensors seldom fail, while crank sensor and fuel pump failures are very common.