VOLVO
ECM-0301 - Misfire cylinder 1.Signal too high
System
Engine Control Module (ECM)
Volvo models this fault code applies to
This fault code has different meanings depending on model, model year or engine. Select the meaning that applies to your car.
Applies to the following models:
3 modelsC30 (2007–2013), S40 (2004–2013), V50 (2004–2013)
Show models by year and engine (14)
- Volvo C30 (2007–2013)2007–2009Engine B4164S3, B4184S11, B4184S8, B4204S3 only
- Volvo C30 (2007–2013)2010Engine B4164S3, B4184S11, B4184S8, B4204S3, B4204S4 only
- Volvo C30 (2007–2013)2011–2012Engine B4164S3, B4204S3, B4204S4 only
- Volvo C30 (2007–2013)2013Engine B4204S3, B4204S4 only
- Volvo S40 (2004–2013)2005Engine B4164S3, B4184S11 only
- Volvo S40 (2004–2013)2006Engine B4164S3, B4184S11, B4184S8 only
- Volvo S40 (2004–2013)2007–2009Engine B4164S3, B4184S11, B4184S8, B4204S3 only
- Volvo S40 (2004–2013)2010Engine B4164S3, B4184S11, B4184S8, B4204S3, B4204S4 only
- Volvo S40 (2004–2013)2011–2012Engine B4164S3, B4204S3, B4204S4 only
- Volvo V50 (2004–2013)2005Engine B4164S3, B4184S11 only
- Volvo V50 (2004–2013)2006Engine B4164S3, B4184S11, B4184S8 only
- Volvo V50 (2004–2013)2007–2009Engine B4164S3, B4184S11, B4184S8, B4204S3 only
- Volvo V50 (2004–2013)2010Engine B4164S3, B4184S11, B4184S8, B4204S3, B4204S4 only
- Volvo V50 (2004–2013)2011–2012Engine B4164S3, B4204S3, B4204S4 only
What does this fault code mean?
The engine control module counts misfires in cylinder 1 and logs a fault when the count exceeds a set limit. A misfire means combustion in that cylinder is missing or uneven, which shows as rough running. The cause may lie in the injection, compression, ignition or fuel.
Possible causes
- Blocked or leaking injector for cylinder 1
- Uneven compression in cylinder 1
- Air leak
- Incorrect fuel pressure
- Fault in the EGR system
- Fault in the ignition system
What you can do
- 1Read the fault code, clear it and road test to see whether it returns
- 2Check that the engine oil is at the correct level on the dipstick
- 3If you have a diagnostic tool, switch off the cylinder 1 injector with the engine at idle and see whether the engine speed changes
- 4Check that the air intake is sealed: listen for air leaks with the engine running
- 5The ignition system works at high voltages. Have a workshop check the cylinder 1 ignition coil and leads and measure compression
- 6If the fault remains, have a workshop check the fuel pressure and the EGR system
Symptoms you may notice5
- Malfunction indicator lamp (MIL) lit
- Engine misfires
- Engine is difficult to start
- Uneven idle
- Engine does not fire on all cylinders
General guidance for car owners. Diagnosis on the car can point to a different cause.