05-06-2010, 09:32 AM
HAULN-SS Wrote:I got the code pulled today: P0420 Catalyst Efficiency low-bank 1
Probably cause: catalytic converter defective failure possibly due to
Engine misfire or running condition
large vacuum leak
engine oil leakage into exhaust valve guide seals, piston rings
I guess I am going to have to get this fixed via a dealer, I can't find aftermarket parts anywhere. I thought about trying to pull one out of a junkyard, but not sure if thats a good idea or not. I also can't find anything online that says whether or not the whole manifold has to be replaced, or if the cat comes off. Anyone ever seen one that was the kind of design before? on gmpartsdirect.com I found a listing for "Catalytic converter, malibu, 2.4l " for $126 but I can't quite tell if that's the one for me, or what it comes with, since there are no pictures
Problem with catalytic converter efficiency codes is that you don't know whether it is an O2 sensor at fault or the cat itself. The same thing happened with my old Taurus GL - I just installed a rear 02 simulator to make the problem go away because I didn't want to pay for a new y-pipe. I would try and replace both 02 sensors (if one is dead the other one is probably about to die anyways) just because it's cheaper, and if that doesn't fix the problem you are going to have to replace the cat as well. If you just replace the cat and the O2s are messed up, it is probably going to kill the new cat with a quickness.
Why do people just post what they are thinking? Without thinking.
2012 Ford Mustang
1995 BMW 540i/A
1990 Eagle Talon TSI AWD
2012 Ford Mustang
1995 BMW 540i/A
1990 Eagle Talon TSI AWD

