I have a 1998 GMC k1500 6.5 turbo diesel. I have all new solenoids (wastegate and 2 for EGR valve). The vacuum pump hits 20 on the guage. The wastegate has about 14 or 15 for vacuum guage. The turbo does spool. I am trying to eliminate the black smoke under hard acceleration. With fair acceleration there is no black smoke. No engine light or codes come up. Has anyone had this problem and got rid of the black smoke under hard acceleration.

 

Ran north this weekend, 800 miles, must have needed a few miles, but no longer an issue.