Code p0420 - Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community

Patsully3 · 02-19-2016, 07:42 PM

I went to the gas station today and filled up and after I did the check engine light came on I checked the fuel cap it was tight I went to auto zone they wernt much help only gave me the error code anyone have ideas? I replaced the headers and exhaust stock front pipe and over pipe

stevesnj · 02-19-2016, 07:48 PM

Thats a bad downstream O2 sensor, the one after the cat. It's catalyst inefficiency code if I remember correctly. Someone will chime in for correct diagnoses on that code.

Patsully3 · 02-19-2016, 08:06 PM

Thank you where is that o2 located so I can change it out?

JB86'd · 02-19-2016, 08:31 PM

you replaced the headers as in...you have aftermarket headers?

FRSBRZGT86FAN · 02-19-2016, 09:39 PM

Quote:

Originally Posted by Patsully3

I went to auto zone they wernt much help only gave me the error code anyone have ideas? I replaced the headers and exhaust stock front pipe and over pipe

You got catless headers and didn't know this code would appear? I think you should've done more research, you need to get a tune to get rid of the P0420 code or do a spacer trick....

FRSBRZGT86FAN · 02-19-2016, 09:40 PM

Quote:

Originally Posted by stevesnj

Thats a bad downstream O2 sensor, the one after the cat. It's catalyst inefficiency code if I remember correctly. Someone will chime in for correct diagnoses on that code.

He has catless headers, and he didn't do any research into what happens when you install them...

Patsully3 · 02-19-2016, 10:05 PM

Yea I got grupee headers form someone on here and a invidia n1 exhaust

Patsully3 · 02-19-2016, 10:06 PM

Quote:

Originally Posted by FRSBRZGT86FAN

You got catless headers and didn't know this code would appear? I think you should've done more research, you need to get a tune to get rid of the P0420 code or do a spacer trick....

Where in Chicago would I get a tune?

Patsully3 · 02-19-2016, 10:06 PM

I've also had them both installed for a lil over a month now and didn't see this issue til now

FRSBRZGT86FAN · 02-19-2016, 10:13 PM

Quote:

Originally Posted by Patsully3

Yea I got grupee headers form someone on here and a invidia n1 exhaust

Quote:

Originally Posted by Patsully3

Where in Chicago would I get a tune?

Quote:

Originally Posted by Patsully3

I've also had them both installed for a lil over a month now and didn't see this issue til now

You have to buy something like OFT and get a off the shelf stage 2 tune, you shouldn't have installed them without knowing the ramifications

in retrospect the Gruppe-s are the best headers on the market for the price.

Also time of when it was installed doesn't matter it's going to come on more and more frequently now, also you'll fail emissions with them without a tune, not only that you're not gaining all the power you can from them without a tune.

Patsully3 · 02-19-2016, 11:13 PM

Yea I'm a noob to this but I'm Keaton and trying but I appreciate the I put and help by any chance know where I can get what I need to make everything alright and work efficiently?

Quote:

Originally Posted by FRSBRZGT86FAN

You have to buy something like OFT and get a off the shelf stage 2 tune, you shouldn't have installed them without knowing the ramifications

in retrospect the Gruppe-s are the best headers on the market for the price.

Also time of when it was installed doesn't matter it's going to come on more and more frequently now, also you'll fail emissions with them without a tune, not only that you're not gaining all the power you can from them without a tune.

FRSBRZGT86FAN · 02-19-2016, 11:41 PM

Quote:

Originally Posted by Patsully3

Yea I'm a noob to this but I'm Keaton and trying but I appreciate the I put and help by any chance know where I can get what I need to make everything alright and work efficiently?

Yup no problem:

http://www.openflashtablet.com/shop/oft-frs-brz-gt86/

It should generate the tune files when you plug it in, mine did but I deleted them so I could edit my tunes personally, but yours should be fine, its $499 and tunes are free

Patsully3 · 02-19-2016, 11:50 PM

So it comes with all the tunes? It's pretty much plug and play?

Quote:

Originally Posted by FRSBRZGT86FAN

Yup no problem:

http://www.openflashtablet.com/shop/oft-frs-brz-gt86/

It should generate the tune files when you plug it in, mine did but I deleted them so I could edit my tunes personally, but yours should be fine, its $499 and tunes are free

Patsully3 · 02-19-2016, 11:52 PM

Is there any other way I mean I'll pay the money if I have to but I'd thought I'd ask and c if there was a cheaper way

QUOTE=FRSBRZGT86FAN;2554642]Yup no problem:

http://www.openflashtablet.com/shop/oft-frs-brz-gt86/

It should generate the tune files when you plug it in, mine did but I deleted them so I could edit my tunes personally, but yours should be fine, its $499 and tunes are free[/QUOTE]

02-19-2016, 07:42 PM	#1
Patsully3 Member Join Date: Aug 2015 Drives: 2014 scin frs Location: Chicago il Posts: 26 Thanks: 0 Thanked 2 Times in 2 Posts Mentioned: 0 Post(s) Tagged: 0 Thread(s)	Code p0420 I went to the gas station today and filled up and after I did the check engine light came on I checked the fuel cap it was tight I went to auto zone they wernt much help only gave me the error code anyone have ideas? I replaced the headers and exhaust stock front pipe and over pipe

02-19-2016, 07:48 PM	#2
stevesnj Senior Member Join Date: May 2013 Drives: 2016 FR-S Oceanic Blue Location: Southern NJ Posts: 2,958 Thanks: 2,158 Thanked 1,601 Times in 923 Posts Mentioned: 30 Post(s) Tagged: 2 Thread(s)	Thats a bad downstream O2 sensor, the one after the cat. It's catalyst inefficiency code if I remember correctly. Someone will chime in for correct diagnoses on that code. __________________ My 2016 Build thread TRD Exhaust with custom quad tips, TRD Lowering Springs,TRD Quick shifter,LED;DRL, Projectors, and turn signals. Re-badge, 86 Nanny, WinmaxW2 Pads, K&N Drop In, Antenna delete

02-19-2016, 08:31 PM	#4
JB86'd Senior Member Join Date: Oct 2013 Drives: JAWS Location: socal Posts: 703 Thanks: 753 Thanked 437 Times in 224 Posts Mentioned: 27 Post(s) Tagged: 1 Thread(s)	you replaced the headers as in...you have aftermarket headers? __________________

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02-19-2016, 08:06 PM	#3
Patsully3 Member Join Date: Aug 2015 Drives: 2014 scin frs Location: Chicago il Posts: 26 Thanks: 0 Thanked 2 Times in 2 Posts Mentioned: 0 Post(s) Tagged: 0 Thread(s)	Thank you where is that o2 located so I can change it out?

02-19-2016, 10:05 PM	#7
Patsully3 Member Join Date: Aug 2015 Drives: 2014 scin frs Location: Chicago il Posts: 26 Thanks: 0 Thanked 2 Times in 2 Posts Mentioned: 0 Post(s) Tagged: 0 Thread(s)	Yea I got grupee headers form someone on here and a invidia n1 exhaust

02-19-2016, 10:06 PM	#9
Patsully3 Member Join Date: Aug 2015 Drives: 2014 scin frs Location: Chicago il Posts: 26 Thanks: 0 Thanked 2 Times in 2 Posts Mentioned: 0 Post(s) Tagged: 0 Thread(s)	I've also had them both installed for a lil over a month now and didn't see this issue til now

02-19-2016, 11:52 PM	#14
Patsully3 Member Join Date: Aug 2015 Drives: 2014 scin frs Location: Chicago il Posts: 26 Thanks: 0 Thanked 2 Times in 2 Posts Mentioned: 0 Post(s) Tagged: 0 Thread(s)	Is there any other way I mean I'll pay the money if I have to but I'd thought I'd ask and c if there was a cheaper way QUOTE=FRSBRZGT86FAN;2554642]Yup no problem: http://www.openflashtablet.com/shop/oft-frs-brz-gt86/ It should generate the tune files when you plug it in, mine did but I deleted them so I could edit my tunes personally, but yours should be fine, its $499 and tunes are free[/QUOTE]

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