406 2.1 12V Diesel - Revving & Knocking!!

Got a 1996 2.1 TD.
At low revs/speeds the engine revvs up to the red line and then cuts out!
Also getting a knocking sound after about 5-10 miles of constant speed - motorway usually.
Also having trouble starting. Sometimes takes 4-5 times to get the bugger started!!
Got a garage to code read - told it was a rotor failure in the fuel pump.
New fuel pump proce £1,400 + VAT!
Got a used one from a breakers fitted - still no good!
Same problems occuring!!!!

DOES ANYONE KNOW WHAT IS WRONG!!!?!?!?!

hey there. did you ever get the problem sorted with your car? my car intermittently revs up on its own and sometimes when i change gear it revs up into the red, scary!
had loadsa people look at it but can not figure it out. Not coming up as a fault on the diagnostics

one thought----check the oil level-ideally it should be just below the maximum line when cold(left standing) it could be pulling oil to the top of the pistons hence the revs and knocks!!

hello did you ever get the problem sorted with your car? my car now revs up on its own and when i change gear it revs up into the red i am going to try changing the throttle potentiometer. just wondered if you ever got it sorted?