10psi is not really a problem. That's actually almost within factory spec for an OM617 turbo (spec is 0.75-0.85 bar at 4000rpm with full load). If the wastegate were stuck open you'd have zero PSI. Not likely you're dealing with a wastegate issue. Sounds much more like the injection pump or injectors. I seriously doubt the timer has failed... I've never heard of one not working, ever.
