E34 Stalling/misfiring problem

["Eugene Hoe" <eugene@xxxxxxxxxxx>]

My E34 525i M20 (1990) is having this very odd intermitted problem. I was
hoping someone could help me out
on this. Ocasionally either when idling or even in the midst of driving, the
car can suddenly lose power and the
engine gets very rough likes its running on 1 or 2 cylinders!. the idle
surges up and down and sometimes stalls
the car. Sometimes it gets so bad that the engine just totally dies and you
can re-start it.

After the car is left for an hour or so it can be restarted but the problem
can reoccur at any time. When the problem
occurs, its almost impossible to rev the engine. Very rough and it seriously
feels like its running on half the number
of cylinders. I trying to figure out what could be causing it? Suspected
areas are fuel pump about to go, distributor
rotor problematic, throttle switch problem, air flow sensor problem (flap
stuck)?. Spark plugs and ignition cable are
new so should be fine.

Anyone got any idea what the problem is or have come across this problem?.
Appreciate all the help. TIA.

Eugene
E34 In a very sick condition.

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