A SCREAM IN THE DARK

I’ve just replaced the EGR valve on my 2008 Subaru Outback diesel. When the car was started, it was making a loud screeching noise. Another problem was that the EML had come on and the fault code ‘P0409 Exhaust Gas Recirculation Sensor A Circuit’ was showing.

A friend who is a former Subaru mechanic instructed the car’s ECU to learn and connect with the new EGR valve. This seemed to work and the EML went off. However, the screeching noise was still there and my friend was convinced it wasn’t the turbo, saying it was more like the sound of air escaping. He then noticed slight exhaust smoke coming from the bottom of the engine. On closer investigation, it was found that one of the bolts for the lower end of the EGR valve pipework, where it goes into the engine block, was loose and the gasket wasn’t making a tight seal. Tightening the bolt up stopped the noise instantly and my mate reckoned the EML light was being triggered due to the lack of pressure in the EGR caused by the leak. So, basically, one loose bolt on a pipe was triggering an EGR fault code and illuminating the EML!