Bad turbo? Need advice (524td)

["Streib, Allan M" <astreib@xxxxxxxxxxx>]

Hi,
    I'm brand new to the list...and I'm looking for some quick information.

    I'm looking at a 1985 524td for sale here. I test drove it and it ran
and pulled well, except as I kept pushing down on the accelerator it reached
a point at which the oil pressure warning light came on and at the same time
I heard a loud buzzing/grinding noise from the engine area. Needless to say
I let up on the accelerator immediately. I tried it once more with the same
results.
    I read in the owner's manual that the oil pressure light doubles as a
turbo overpressure warning. But what about that awful noise? Is it a warning
buzzer of some kind or is this thing about to die?
    Other than this the car seems to be in fairly decent mechanical
condition. Thoughts appreciated before I decide whether to buy
Allan

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