Code P0420 Catalyst System Efficiency Below Threshold (Bank 1)?

[jacek82]

I got a P0420 on a 98 Mountaineer V8 89,000 Miles.
Recently I replaced all the O2 sensor about a 1.5 yrs ago.
P0420 Catalyst System Efficiency Below Threshold (Bank 1). What else could it be? I checked the obd2 and this is what it computer showed me but not sure what it means.

Freeze Frame (Frame 0) for DTC P0420
Calculated Load: 40 %
Coolant Temperature: 189 F
Engine RPM: 1408 r/min
Fuel System Status Bank One: Closed Loop
Fuel System Status Bank Two: Not Reported
Long Term Fuel Trim Bank One: -3.90 %
Long Term Fuel Trim Bank Two: -3.90 %
Short Term Fuel Trim Bank One: -2.34 %
Short Term Fuel Trim Bank Two: -0.78 %
Vehicle Speed: 17 MPH

Any info would help.

Jack

 

[jacek82]

ttt

 

[Ranger379]

subscribing, i got this just the other day too, as well as every now and then

just found this site: http://www.obd-codes.com/trouble_codes/generic/p0420-catalyst-efficiency-below-threshold-bank-1.php

 

[raaizin]

I hade the same code....I bought 02 fooler and passed emission. Either that or replace the Cat. For $10.00 it was well worth it....No more check engine light...Ray


Here is a lilink where I got mine from:
http://www.brickauto.com/o2bypass/o2bypass.htm

 

[Ranger379]

didnt know there was such a thing as 02 fooler. hows it hook up? sounds cheaper than replaceing the cats, i think thats what wrong with mine cause they are really rusty for one. and two when i bought it the muffler was only held together by an act of God LOL so almost rusted from one side to the other lol.

 

[raaizin]

Here is how to install:


http://www.brickauto.com/o2bypass/o2install.htm
I did mine without removing my rear O2 from the car. Very easy job.

Good Luck