The car has 150,000 Km's (90,000 miles?). It has been flawless, until the MIL - P0420. Subaru dealer wanted to play "Replace parts til he's broke" I have changed the rear O2 sensor, now have a new catalytic converter. I do not wish to just keep throwing parts at it. I thought that a Subaru dealer should have the equipment to look at the ECM inputs and O2 outputs, etc... HELP... if anyone has experienced this or something like it, I would appreciate any help. Where do I go from here, BROKE ??
98 Legacy OBD2 code P0420
Oct 09, 2004
2 Replies
What does that code mean? TG
OK, low catalyst efficiency. Usually replacing the exhaust manifold gaskets will cure this. I like to replace or at least chase the studs, you need an accurate torque reading here. Check for any other exhaust leaks upstream of the O2 sensors. TG
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