Land Rover Repair: engine stalls, film canister, fuel pressure

Question
what's up
well i have a96 RR 4.0 se it turns off some times after i make a stop and i get going
i scanned it and i got 2 codes  (1) P0727 (engine speed presence of rising or falling edges)  (2) P1775 gear boxfault  
i replaced the ckp and cleared the code but it continues to stall i tested the fuel pressure and i got   38psi ignition switch on engine off  and 30psi with the engine running is this normal on the fuel pressure
need all the help and advice you can give me     thanks

Answer
the gearbox fault comes as a result of the stall, ignore that.  

the most common reason for stalling is a gunked up Idle Air stepper motor, it's on the throttle body, looks like a 35mm film canister.  Remove it and clean with a can of carborator/choke cleaner.  That will probably cure the stalling.