I have a 2004 Discovery with a 140 thousand on it. Last year just to be preventative I replaced the oil pump. Lately it appears the idle is lower than normal and as a result the oil light comes on. If you shift into neutral the engine revs slightly and the light goes off. Would this issue be related to the cam shaft position sensor or something else? It does not happen all the time, just when the rpm seems to drop below 700rpm at idle. Thanks for any help.

 

What type of oil are you running?? You should do a PSI test to see what your actual oil psi is.

 

Rottela 15W-40

 

X2 on the manual gauge test. Might have sludged up oil pickup, etc.