Description
OBD-II Trouble Code Description for P0421 Ford
Warm Up Catalyst Efficiency Below Threshold
What does this mean?
OBD2 Code P0421 Ford definition:
Basically this means that the oxygen sensor downstream of the catalytic converter on bank 1 is detecting that the converter is not working as efficiently as it should be (according to specs). It is part of the vehicle emissions system.
Symptoms
Possible sumptoms of OBD code P0421 Ford
You will likely not notice any drivability problems, although there may be symptoms. The code may be more likely to occur after the engine has had numerous cold starts in the past 1-2 days.
Causes
Possible causes of OBD code P0421 Ford
A code P0421 Ford may mean that one or more of the following has happened: The catalytic converter is no longer functioning properly An oxygen sensor is not reading (functioning) properly A sparkplug is fouled up
Possible Solutions
Measure the voltage at the oxygen sensor on Bank 1 (the rear sensor, or the sensor after the converter). In fact, it would be a good idea to test each oxygen O2 sensor while you’re at it. One thing to note is that many vehicle manufacturers offer a longer warranty on emissions-related parts. So if you have a newer car but it’s out of it’s bumper-to-bumper warranty, there still may be warranty on this type of problem. Many manufacturers give a five year, unlimited mileage warranty on these items. It’s worth checking into.
The OBD2 Code Information Be Applicable For Ford:
2013 Ford Taurus,2013 Ford Mustang,2013 Ford Kuga,2013 Ford Fusion,2012 Ford Focus,2011 Ford Mondeo,2011 Ford Focus,2011 Ford Edge,2010 Ford Mustang,2009 Ford Focus,2008 Ford Fiesta,2008 Ford Escape,2007 Ford Mondeo,2006 Ford Focus,2005 Ford Mustang,2005 Ford Escape,2003 Ford Mustang,2003 Ford Focus,2000 Ford Mustang
Note:
1. The list of automotive Makes at the right edge of the screen. The currently selected ODB-ii codes is for the Ford makes.
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