Did you try cracking the injector nut at the injector, one at a time while the engine is running? Fuel should spray out of each and the idle note should change as each nut is cracked.

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85 300D turbo pristine w 157k when purchased 167,870 July 2025
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked