Description
OBD-II Trouble Code Description for P0420 Fiat
Catalyst System Efficiency Below Threshold
What does this mean?
OBD2 Code P0420 Fiat definition:
The catalytic converter has an oxygen sensor in front and behind it. When the vehicle is warm and running in closed loop mode, the upstream oxygen sensor waveform reading should fluctuate. The downstream O2 sensor reading should be fairly steady. Typically the P0420 Fiat code triggers the Check Engine Light if the readings of the two sensors are similar. This is indicative of (among other things) a converter that 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 P0420 Fiat
You will likely not notice any drivability problems, although there may be symptoms.
Causes
Possible causes of OBD code P0420 Fiat
A code P0420 Fiat may mean that one or more of the following has happened: Leaded fuel was used where unleaded was called for An oxygen sensor is not reading (functioning) properly The engine coolant temperature sensor is not working properly Damaged or leaking exhaust manifold / catalytic converter / exhaust pipe Retarded spark timing The oxygen sensors in front and behind the converter are reporting too similar of readings
Possible Solutions
Some suggested steps for troubleshooting a P0420 Fiat error code include: Check for exhaust leaks at the manifold, pipes, catalytic converter. Repair as required. Use a scope to diagnose the oxygen sensor operation (Tip: The oxygen sensor in front of the catalytic converter normally has a fluctuating waveform. The waveform of the sensor behind the converter should be more steady). Inspect the downstream heated oxygen sensor (HO2), replace if necessary Replace the catalytic converter 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. See also: P0420 Fiat.com – P0420 Fiat Help
The OBD2 Code Information Be Applicable For Fiat:
2013 Fiat Viaggio,2013 Fiat Strada,2013 Fiat Panda UK Version,2013 Fiat Panda Trekking,2013 Fiat Panda 4×4,2013 Fiat Panda,2013 Fiat 500S,2013 Fiat 500L,2013 Fiat 500C Abarth,2012 Fiat Punto,2012 Fiat Palio,2012 Fiat Freemont AWD,2012 Fiat Freemont,2012 Fiat 695 Abarth Maserati Edition,2012 Fiat 500 Abarth,2011 Fiat Uno,2011 Fiat Punto Evo Abarth esseesse,2011 Fiat Punto Evo Abarth,2011 Fiat Idea,2011 Fiat Bravo,2011 Fiat 500 Sport,2011 Fiat 500 Coupe Zagato Concept,2011 Fiat 500C Abarth esseesse,2011 Fiat 500C Abarth,2010 Fiat Uno Cabrio Concept,2010 Fiat Sedici,2010 Fiat Punto Evo,2010 Fiat Doblo Cargo,2010 Fiat Doblo,2010 Fiat 500 Abarth R3T,2010 Fiat 500C,2009 Fiat Grande Punto Natural Power,2009 Fiat Fiorino Qubo,2009 Fiat 695 Abarth Tributo Ferrari,2009 Fiat 500 Barbie Concept,2009 Fiat 500 Abarth esseesse,2009 Fiat 500 Abarth Assetto Corse,2009 Fiat 500 Abarth,2008 Fiat Portofino Concept,2008 Fiat Panda Cross,2008 Fiat Grande Punto Abarth,2008 Fiat Grande Punto,2008 Fiat Fiorino,2008 Fiat Croma,2008 Fiat Bravo 1.6 Multijet 16v,2008 Fiat 500,2007 Fiat Panda 100HP,2007 Fiat Linea,2007 Fiat Grande Punto Abarth S2000,2007 Fiat Grande Punto Abarth Preview,2007 Fiat Bravo,2006 Fiat Ulysse,2006 Fiat Sedici,2006 Fiat Panda Multi Eco Concept,2006 Fiat Panda Cross,2005 Fiat Panda Alessi,2005 Fiat Panda 4×4 1.3 Multijet,2005 Fiat Oltre Concept,2005 Fiat Idea,2005 Fiat Grande Punto,2005 Fiat Doblo Cargo,2005 Fiat Doblo,2005 Fiat Croma,2005 Fiat 600 50th,2004 Fiat Trepiuno Concept,2004 Fiat Strada Malibu,2004 Fiat Stilo M.Y. 1.9 Multijet 5door,2004 Fiat Seicento,2004 Fiat Punto Rally,2004 Fiat Panda 4×4,2004 Fiat Multipla,2004 Fiat Idea 5terre Concept,2003 Fiat Strada,2003 Fiat Punto Sporting,2003 Fiat Punto Rally,2003 Fiat Punto Natural Power,2003 Fiat Punto Dynamic,2003 Fiat Punto Active,2003 Fiat Panda Emotion,2003 Fiat Panda Dynamic,2003 Fiat Panda Actual,2003 Fiat Panda,2003 Fiat Marrakech Concept,2003 Fiat Idea 1.9 Multijet Dynamic,2003 Fiat Idea 1.4 16v Emotion,2003 Fiat Idea,2003 Fiat Barchetta First Class of Alviero Martini,2003 Fiat Barchetta,2002 Fiat Ulysse Emotion 2.0 16v,2002 Fiat Ulysse 2.0 JTD,2002 Fiat Ulysse,2002 Fiat Stilo Multi Wagon Dynamic,2002 Fiat Stilo Multi Wagon Actual,2002 Fiat Stilo Multi Wagon,2002 Fiat Stilo Dynamic,2002 Fiat Stilo Active,2002 Fiat Stilo Abarth,2002 Fiat Stilo,2002 Fiat Simba Concept,2002 Fiat Palio Weekend,2002 Fiat Palio,2002 Fiat Multipla,2002 Fiat Albea,2001 Fiat Doblo
Note:
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