Derate and 20 psi boost due to EGR short or voltage below normal

[Rawze]

The engine brake fault is not normal. egr valve acting up will not cause this. That issue needs to be fixed.. likely a loose connector under the valve cover, those clips become loose. That or the engine brake plug saturated with oil/sludge due to blo-by.

The intake pressure sensor likely needs replacing. Might as well replace the other one and the exhaust pressure sensor, and check its feed circuit too.

Turbo inlet temp alarm above normal is usually an indication that the turbo is overheating or being abused in some way. Likely overheating due to low boost. -= Might also want though to ensure the exhaust muffler is not getting plugged up. If it is more than 8-10 years old and has a million+ on it, .. its time to replace the muffler while your at fixing the rest.

As far as the egr valve... forum member 'running rough' does CM870's for people on here.

Might also want to do a turbo inspection etc. while your at it too.