VOLVO
ECM-4438 - Exhaust gas recirculation (EGR) control. Jammed
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
3 modelsC30 (2007–2013), S40 (2004–2013), V50 (2004–2013)
What does this fault code mean?
The engine control module (ECM) monitors EGR control. When the valve jams, for example from soot or dirt, and does not follow the control signals, the code is set. The fault can also come from the wiring or connectors to the valve.
Possible causes
- Loose connections, contact resistance or oxidation at the EGR valve terminals
- EGR valve jams, for example from dirt or soot
- Break in the wiring to the EGR valve
- Wiring to the EGR valve shorted to ground or supply voltage
- Damaged EGR valve
What you can do
- 1Read off and note the fault code, erase it and test-drive the engine to see whether it returns
- 2Look at the EGR valve connector to see whether it is loose or oxidised
- 3Check mechanically whether the valve is clogged with soot and sticking
- 4With a multimeter you can check for a break and for contact with ground in the wiring to the EGR valve
- 5If the fault remains, have a workshop with diagnostic equipment check the valve and its wiring
Symptoms you may notice2
- Message shown in the text display
- Check engine light lit
What the fault can affect2
- EGR control is disconnected
- Engine output is limited
General guidance for car owners. Diagnosis on the car can point to a different cause.