engine will not come up to full rmp. H50 D 394 series with a VW BJC diesel engine, turbo charged. turbo was built in Nov. just replaced the injector pump and speed sensor. ran compression check and had good compression.

engine will not come up to full rpm and drive will drop out a little over half way. I can play with the hyd lift lever and get the engine to come up to speed and then drive it and it will run full speed. anybody have any ideas.