Dodge Nitro Forum banner

1 - 5 of 5 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter #1
Hello all,

I have a 2011 Heat 3.7L and out of the blue it started throwing codes for catalytic system not running well. I know I can switch out the O2 sensors easily but that was not what the codes (p420 and p430) were saying was the issue. Could they be the reason for the error codes but not be throwing their own failure error?

So talked to the dealership and another garage and they both want thousands to fix which I just do not have. Looking at AutoZone site, I saw that there are universal ones that are as low as $88 so I wondered what was the drawback of choosing something from there. Doesn't have to be super cheap but that would save me a lot of cash.
 

·
I work so I can... SQUIRREL!
Joined
·
2,513 Posts
Most common causes for these codes is:
  • The catalytic converter is no longer functioning properly
  • An oxygen sensor is not reading (functioning) properly
  • There is an exhaust leak
I would first inspect the entire exhaust system (particularly near engine and catalytic converter) for leaks. If one is found, repair it, as this may be the problem. If the system has no leaks, check the O2 sensor connections and wiring. You may have a loose connection or a wire may have been scorched by the exhaust heat.

If O2 sensors are replaced, and the problem remains, then you may have a fuel delivery issue, such as running too rich or too lean. The catalytic converter will normally last a good while (or a good +/-10 years or better). While it is possible that the converter is bad, it is usually unlikely.
 

·
Registered
Joined
·
437 Posts

·
Khaki Nitro Nut
Joined
·
30,201 Posts
Do you have the full code #?
Are they?
P0420 Catalytic converter system, bank 1 - efficiency below threshold. Possible causes; Catalytic converter, wiring, HO2S 2
P0430 Catalytic converter system, bank 2 - efficiency below threshold. Possible causes; Catalytic converter, wiring, HO2S 2

If you replace 1 o2 sensor on one bank without replacing the other (new front sensor and old rear sensor on one bank).
This will set these codes.
 

·
Registered
Joined
·
437 Posts
Any progress here?

Maybe you can describe what you did. Root causes for catalytic converter efficiency below threshold can be very different.

  • Bad fuel.
  • Unmetered intake leak or incorrectly measuring MAP sensor.
  • Exhaust leak in exhaust manifold.
  • Issue with ignition. Worn spark plugs, broken ignition coils.
  • Pre-cat O2 sensor old (slow reponse) or contaminated and forcing mixture to very lean. (Could be silicone spray used close to intake or coolant leak into combustion chamber)
  • Post-cat O2 - same issues as pre-cat O2
  • Something wrong with injection system - low pressure, clogged injectors? Leading to lean mixture. Rare I think.
  • Bad catalytic converter.
 
  • Like
Reactions: Metaldog
1 - 5 of 5 Posts
Top