VEHICLE: 2011 Volvo XC60
ISSUE: Abnormal noise from engine bay when driving
DIAGNOSIS & SOLUTION:
A customer of ours has a 2011 Volvo XC60 and they are complaining of an abnormal noise from the engine bay when driving. We have heard the noise on road test but we are having difficulty finding the source of the noise in the workshop. Do you have any ideas what could be causing this noise?
Yes, we have heard of the issue you have described and it affects Volvo models with a 5-cylinder Diesel engine. The noise is caused by the exhaust gas recirculation (EGR) valve resonating due to vacuum pressure fluctuations caused by deterioration of the brake servo vacuum pump non-return valve. Fit a modified brake servo vacuum pump non-return valve (fig. 1.1.). Check operation of the exhaust gas recirculation (EGR) vacuum control solenoid and replace if necessary. Carry out road test to ensure noise has been eliminated.