Description
OBD-II Trouble Code Description for P0421 Porsche
Warm Up Catalyst Efficiency Below Threshold
What does this mean?
OBD2 Code P0421 Porsche 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 Porsche
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 Porsche
A code P0421 Porsche 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 Porsche:
2013 Porsche Cayenne,2013 Porsche Boxster S,2013 Porsche Boxster,2013 Porsche 911,2012 Porsche Panamera,2012 Porsche 911,2011 Porsche 911,2010 Porsche Panamera,2010 Porsche Cayenne,2010 Porsche 911 GT3,2009 Porsche 911,2008 Porsche Cayenne,2008 Porsche Boxster,2008 Porsche 911,2007 Porsche Cayman,2007 Porsche Cayman,2007 Porsche Boxster,2007 Porsche Boxster,2007 Porsche 911,2006 Porsche 911,2005 Porsche Boxster S,2005 Porsche Boxster,2005 Porsche 911,2004 Porsche 911,2003 Porsche 911
Note:
1. The list of automotive Makes at the right edge of the screen. The currently selected ODB-ii codes is for the Porsche makes.
2. Look up the other OBD II Trouble Codes, please use the search box. Enter the 5 character trouble codes in the search box and submit the search.
3. Don’t assume a particular OBD-II code means the same for other auto manufacturers as there are many makes specific codes in use.
4. If your OBD-II trouble codes are for a different car, select that vehicle series before searching for the diagnostic codes because not all OBD2 codes used by one manufacture are used by the other makes.
5. The information contained on this site is presented for informational purposes only. We are not responsible for any actions you take on your vehicle. If you have any doubt as to repairs on your vehicle, please contact your technician.