What’s this do ?

Just noticed this, sorry it's so late, but I'm honestly surprised no one jumped in right away.

It's the engine shut-off for a mechanical diesel. It acts on the IP to cut off the fuel feed, since a diesel has no ignition to switch off. Pull to stop the engine, release and it returns under spring tension. Mine was in place of the choke pull that would have been on a petrol model. Any chance your 88 started life as a diesel? Or did someone use this as a choke knob because it was lying about?

Thanks…. Wasn’t hooked to anything. So just removed it.

Hang on to it. Useful as a spare choke knob. It would also be useful to all the guys swapping OM617's into their Land Rovers. It has a mechanical stop as well.