VOLVO
ECM-4477 - Exhaust gas recirculation (EGR) control. Flow too low
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 and finds a fault that causes too little exhaust gas to be routed back compared with what is needed. The code is set when EGR control is incorrect, and the cause may be the valve, its wiring or an air leak in the intake.
Possible causes
- Poor contact, contact resistance or oxidation at the EGR valve connections
- Dirt or soot makes the EGR valve stick
- Break in the wiring to the EGR valve
- Air leak in the intake system
- Damaged EGR valve
What you can do
- 1Note the fault code, erase it and test-drive to see whether it returns
- 2Check that the EGR valve connector is firmly seated and free from oxidation
- 3Look at the valve for soot and dirt that may restrict the flow
- 4Look for cracks, loose hoses and other leaks in the intake air, since a leak affects EGR flow
- 5With a multimeter you can check that the wiring to the EGR valve has no break
Symptoms you may notice2
- Emissions warning lamp is on
- Message shown in the text display
General guidance for car owners. Diagnosis on the car can point to a different cause.