Catalytic converter costs

SOURCE: Please Help... p0404 and p0137 Error Codes (1999 Saturn SL1)

yes egr valve is a common thing on this saturn. very pricy and yes you need the rear o2 sensor good luck i have a used egr if interested off a sl2

SOURCE: 2004 Chevy Blazer O2 Sensor

there are two 02 sensors actually on the engine. bank one is cylinders 1 3 5 bank 2 is 2 4 6. it controls the fuel to air ratio, if the O2 sensor is not working, the engine goes into limp mode, which means it is just putting as much fuel as possible into the cylinder, which will effect your gas mileage.

The O2 sensor may be fine, the pigtails off the 02 sensor go bad, the connection. I had in my car, i change the 02 sensor twice, then I found someone said the pigtails may be bad, so I cut the cars wiring harness pigtail, and the one coming off the 02 sensor, and directly wired it with the original truck 02 sensor, and it worked. all 02 sensors look similar, they screw in the side of the engine, and just have 4 wires coming off of it.

Try your origional one, and just bypassing the original wire connector, what I did was cut it off, skinned the wires, put some heat shrink rap on it, combined the wires together soldered them together, and heated the wire shrink rap, so that way it is water proof. car works perfect now.

SOURCE: Replaced 0xygen sensor in 2003 Hyundai Accent 3 Times Not Fixed!

It sounds like you have either a lean or rich condition ocurring,could be exuast leak,vac leak,leaking fuel preasure regulator,cat convertor.At this point would go to dealer for diagnosis.

SOURCE: Catalytic Converter for Honda CRV 2002- cost/necessity of repair

run scanner for trouble codes, some auto parts stores will do this for free

SOURCE: 2001 Honda - New Catalytics & O2 sensors -- new 0420/1739/1456

I would send the car for a smoke test for the emissions leak...Find out where the leak is comming from..Repair it..Reset the codes, then do a drive cycle and see what happens...