Land Rover Repair: p0335, crankshaft sensor, crank sensor

Question
I have  a 99 disco. II that dies on me with code p0335 & 1590,i have replaced the crankshaft sensor with a factory one but now it start rough when its cold but 10 minutes later when it warm it smooth out but when i rev it wont pass 1200 hundred rpm, it stalls the check engine light goes on and off as i rev it.I clear the codes but it keeps coming back with P0335 & p1590.

Answer
You may have a problem with the reluctor plate on the flywheel . . . it makes the signal the crank sensor picks up.

If your car were here we'd look at the crank sensor signal with a lab scope and see if it was irregular.  If it was, the first step would be to pull the sensor and check it, and the second step would be to pull the transmission and check the flywheel for damage.

We get 1-2 Rovers every year with bad plates on the flywheel.