Nissan Largo Friends

Given the engine will run without it, there's a possibility it has been removed by the previous owner. It should be there to the left and slightly above the lower crank. The loom connector for it is up by #1 injector, look for a connector with nothing fitted.

Ok been under my van again checking for the cps I've checked from the sump all the way up to the water pump and cant see a thing? sorry I know this might seem stupid but do i need to removed the black plastic cover between the crank and water pump
That cover comes all the way down the side to the sump

No you don't need to remove that cover to get to it. Does sound like it's missing!

I checked both sides to be honest I dont think this engine has ever had one there isn't any room for it to be fitted