Hey Everyone,
Im doing a throttle body inspection, this one here:


And I have no vacuum @ 3500 rpm or higher on the R line leading from the throttle body to the EGR modulator. Anyone have an idea why?

 

Sounds like you have carbon or oily gunk buildup in the throttle body that is obstructing the port. Take the vacuum hose off the fitting at the throttle body and spray some throttle body cleaner into the port and look into the throttle body opening to see if the spray goes into the throttle body. This should clean it out and allow vacuum with the engine running. I'd clean all three ports while you're there. If you still don't have vacuum at the EGR modulator, the hose itself must be obstructed and should be replaced.

 

I'd recommend to check the vacumm port at the throttle first. Mine has corroded and clogged. I used a paper clip to clean it. If the R port at the throttle happens to be clogged, check the rubber hose to see if it is not clogged too. Good Luck!!