SPN 2791 FMI 7 — EGR valve — not responding
Applies to: Detroit · Navistar · Paccar · Volvo · MaxxForce 13 very common · Very common on D13
EGR valve — not responding.
Your SPN/FMI rides along, so nearby mechanics see the fault before they quote you.
How serious is it?
Serious. Power derate likely — plan to stop soon.
Most likely causes
- Carbon packing on valve
- Valve stuck
- Actuator failed
- Carbon
- Actuator
- Carbon buildup
- Actuator failure
First moves (roadside)
- Inspect EGR valve for carbon
- Actuation test
- Inspect EGR
- Inspect valve
- Inspect EGR valve
Common misdiagnoses
- Replacing valve without inspecting stem
- Replacing before inspecting
FAQ
EGR valve — not responding.
Serious — Power derate likely — plan to stop soon.
The most common cause is: Carbon packing on valve. Other possibilities include Valve stuck; Actuator failed; Carbon; Actuator; Carbon buildup; Actuator failure.
Power derate likely — plan to stop soon. When in doubt, get a qualified mobile diesel tech on the truck before continuing.
Find a mechanic or related guides
General diagnostic guidance for heavy-duty diesel engines (Cummins, Detroit, PACCAR, Volvo, Mack). Not a substitute for a scan-tool diagnosis on your specific truck.