Catalytic Converter help!! P0420

[gCobalt05]

My CEL was on today and I went to get the codes pulled for it and came up with P0420. The guy said my catalytic converter was low efficiency bank 1.
Not sure what this means but they said it would cost $380.00 plus extra for labor.

What do I do? I dont know much about getting a new cat converter.
I'm at 72000 miles if that helps anyone. Thanks guys!

 

[wardzach2007]

http://www.obd-codes.com/p0420

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 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.

Causes

A code P0420 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 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.

 

[Jn2]

it probably a bad cat, go on the .net and buy urself a new downpipe, should cost u more than 100 for a LSJ one, and its a performance upgrade...and u'll be set, install can be done in ~30mins...do it urself and save urself the time and money from doing it at a shop...if you were local i would do it for you for $20 to cover time and labor hell i had a few stock downpipes here but i got rid of them a week ago, like i said post a WTB: LSJ downpipe and ur set

 

[gCobalt05]

it probably a bad cat, go on the .net and buy urself a new downpipe, should cost u more than 100 for a LSJ one, and its a performance upgrade...and u'll be set, install can be done in ~30mins...do it urself and save urself the time and money from doing it at a shop...if you were local i would do it for you for $20 to cover time and labor hell i had a few stock downpipes here but i got rid of them a week ago, like i said post a WTB: LSJ downpipe and ur set

So a new DP and header?
Thats what Ive read somewhere else too?

 

[Jn2]

no just a new DP, u dont need a header, but if you find someone selling a LSJ header/dp together for a good deal go for it, but u only really need just the downpipe alone

 

[Cobalt Tom]

wait, arent cat's warrantied by law up to like 100k miles and 8 years or something??

 

[gCobalt05]

no just a new DP, u dont need a header, but if you find someone selling a LSJ header/dp together for a good deal go for it, but u only really need just the downpipe alone

Ok thanks jn2. and since the DP is a performance upgrade, what does that do? Free up horses?

 

[asherby85]

I think it should be warrantied.. Take it to the dealership first and find out.

If not, then I'll have a reg 2.2 DP that you can buy off me real soon, and I will sell it to you for dirt cheap. Otherwise go for the LSJ one, it'll cost ya tad more but will a performance upgrade.

---------- Post added at 07:29 PM ---------- Previous post was at 07:29 PM ----------

Ok thanks jn2. and since the DP is a performance upgrade, what does that do? Free up horses?

The diameter of the DP is bigger than what's on your car right now. Bigger diameter = better breathing = more horsepower

 

[Cobalt Tom]

i have a buddy swapping out a 2.0 header and dp this weekend at my place, ill have him post up with what he would want for it if you want maybe he'll cut you a killer deal since im doing the install

 

[Jn2]

wait, arent cat's warrantied by law up to like 100k miles and 8 years or something??

true he may want to check into that, but i mean ths would be the ideal time to change over to a LSJ gheader/dp free up some horsepower...