My Frind has a 2006 Ford F-350 4x4 6.0l turbo and got under boost P0299

[Joseph Davis]

I checked the exhaust back pressure and it seemed to be on the higher values of the ranges set on my OTC Genisys 5.0 ford diagnostic scanner, does this mean the door to exhaust gate stuck shut or is it building to much heat because of lean condition because of clogged injectors or dirty fuel filter. I am new to Diesel but work on cars most of my life.

 

[79jasper]

Sticking unison ring is common.
But it shouldn't cause high back pressure and low boost. Unless there's a boost leak also. Which is also common.

Sent from my SM-G892A using Tapatalk

 

[SebastIDIan]

Bad ebp sensor or clogged ebp tube can cause underboost so can leaky cac boots/tubes. Stuck VGT vanes in the turbo as well. 6.0 dont have a wastegate.

Edit: x2 on jasper he beat me to it

 

[Joseph Davis]

I did find an air filter leak on intake so the air coming in to what the boost creates might have been the under boost condition because it was pulling air in unmetered? He found the clip that was missing under the air filter Box. Now on the Stuck VGT vanes that is what creates the boost pressure in exhaust? how far they open?