I just replaced my o2 sensor. The heat shield was rattling and so i took it off. I still get this goddamn ratting what could it be? Also my car kind studders everyonce and a while. It looks like the cause might be this little valve/solinoid on the firewall that has two or three hoses running into it. Is that the egr solinoid?

 

The EGR solenoid is grouped together with all the other (emissions) solenoids under the upper intake manifold.&nbsp I highly doubt what you're describing is the EGR solenoid...


-Ted