Check engine! P0420

[caliboy15]

P0420 Catalyst System Efficiency Below Threshold (Bank 1)

I got this code after installing

Cobb DP
FSwerks exhaust
Mountune Full induction kit

no tune, tried stage 1.. no luck!

I will be installing Mountune FMIC tomorrow and run stage 3

any idea why Im getting this code?

 

[JPGC]

It's probably due to the high flow cat on the Cobb downpipe. Sometimes high flow cats will throw that code just like a race downpipe. Are you planning on running stg3 once you get the intercooler on. If so, the tune has that code deselected so that you won't throw that code. Lol, just reread your post...you should be fine with Stg 3 once you install it. If not..check your connections from where you installed the downpipe.

 

[caliboy15]

yeah I will be running stage 3 tomorrow asap. Im getting paranoid seeing the code today.

 

[JPGC]

Try installing the Stg 3 now to see if it goes away. Just don't be driving crazy and going wot...or at least keep an eye on your charge temps while driving.

 

[BoostBumps]

P0420 Code Disable

FYI...

No surprise that you threw a P0420 code after installing the DP with high flow CAT without disabling the P0420 code...

Just verified quickly by reviewing Stg 1,2, & 3 OTS maps and see that Cobb only disables the P0420 DTC code (see box uncheck) in their stg3 OTS map...

You should be fine after you install the FMIC and load stg3 map...

 

[caliboy15]

Thanks guys, I will be installing the fmic tomorrow and will do stage 3

 

[iso100]

I've been driving with the CP-E downpipe (catted) and don't have any codes...

 

[JPGC]

Some do and some don't with high flow cats.

 

[iso100]

Ahh, maybe spending nearly $700 for a catted downpipe (OMG) was a good thing. Of course now I'm just an FMIC away from stage 3. Wallet goes running...

 

[Kip2MyLou]

Or just a tune from somebody who can get of that code for you.

 

[iso100]

Or just a tune from somebody who can get of that code for you.

That just shuts off display of the code. Emissions checking will still find it and fail you.

 

[Kip2MyLou]

A lot of people don't have emissions though. And isn't that all Cobbs stage 3 map does, turn it off? With their catted DP.

 

[lessard.dcj]

i was throwing the code with my 2j DP with defouler in the warmer months. since winter though i have not seen it back, i wonder if the temps have something to do with it

 

[iso100]

A lot of people don't have emissions though. And isn't that all Cobbs stage 3 map does, turn it off? With their catted DP.

Yes. I'm speaking for myself though. I have the Cp-E catted and also have to do emissions.

I'm just happy that so far I haven't thrown any codes.

 

[iso100]

i was throwing the code with my 2j DP with defouler in the warmer months. since winter though i have not seen it back, i wonder if the temps have something to do with it

Yikes. I guess I'll have to wait and see...

 

[BryanD]

Your upstream O2 sensor (between turbo and cat) reads the air fuel mixture before the cat by switching back and forth from about .1V to .9V. After the catalytic converter, the downstream 02 sensor likes to see a very steady reading of about .5V. If you have a high flow downpipe, the catalytic converter isn't doing as much of its job concerning emissions as your factory downpipe. Your downstream o2 will switch between .1V and .9v like the upstream one, which is what triggers the p0420 code. I do not recommend using o2 spacers or defoulers. Get a proper tune that is optimized for a high flow downpipe (Cobb OTS tune works great). Otherwise your air fuel mixture may not be as spot on as it could be, and you could be running slightly too lean under full boost.

Also for who was throwing codes in the summer, but not in the colder temperatures. Remember that vehicles are very smart, and will alter fuel delivery based on not only the amount of air, but the temperature of the air since the temperature changes the density of the air!

My advice is throw a solid tune on it even if you aren't throwing codes to be sure you're safe and keep your engine running happy for many years.

-certified tech

 

[caliboy15]

running stage 3 now! no more code

 

[BoostBumps]

running stage 3 now! no more code

glad to hear! enjoy!

 

[JPGC]

running stage 3 now! no more code

That's all your gonna say, lol. It's good that your code is gone but how do you like the transformation so far?

 

[caliboy15]

haha sorry been busy driving. it feels great! i dont see myself going back to stock. i want more!!