Extremely frustrated. Chasing 2359 low boost for a while. 261000 miles. Passed SMOKE & pressure test. Have replaced everything in system except the PCM and the swirl valve actuator. Removed manifold and cleaned, inspected actuator, and can see activation. Happens around 55 MPH, but varies with times and mileage. BOOST pressure is different than SET pressure by 200 HPA when code sets & limp occurs. However these only match at high accel or coastdown. At idle differ about 30 HPA. Dealer Sprinter Tech says: Checked all previous repairs. All OK. Advised possibility of swirl valve and/or PCM replacement. Could not verify WHICH is necessary. No guarantee that either one would fix the issue, and parts not returnable. What the He!!. PCU is $2K. Any ideas or someone from the manufacturer end to talk too?

John Isaacson
Owner/Technician
Ike's Repair Inc
Hudson, Florida, USA