03 Baja exaust problems

Technical Discussions - Got a mechanical problem?

Moderator: bajabob

Post Reply
BasilLee
Scoobytruck Lurker
Posts: 1
Joined: Sat May 04, 2019 6:54 am

03 Baja exaust problems

Post by BasilLee » Sat May 11, 2019 2:07 pm

So are all Suby Baja's in 03 programed for California emissions? & how do I get around it? I live in NC but my Suby won't pass NC emission test because of the check engine light which is because Of my catalytic converters which are new but Not thinking about it & it said where I ordered them not for California emissions My mechanic said I need the $1,0000.00 set which is what my car is programed for. I bought what I thought was a good set $385.00 but won't pass. I've put a new Jegs motor in it New exhaust sensors & new exhaust front 2 back. but didn't notice little sticker under hood that said programed for California Emissions??? Any Ideas I need help or another good Suby body without that durn cali sticker. I have a year to figure it out got passed for now but light is back on didn't last 50 miles?? I need help?? It also causes a build up some times which causes it to smoke once in a while when you 1st start it up not all the time & I know motor is good it's new wondering about leaking fuel injector??
Last edited by BasilLee on Wed Jun 19, 2019 9:19 pm, edited 2 times in total.

Airborneguy
Scoobytruck Contributer
Posts: 40
Joined: Thu Feb 22, 2018 6:21 pm

Re: 03 Baja exaust problems

Post by Airborneguy » Sun May 12, 2019 10:31 am

Space the front O2 sensor out and you should be fine. That’s what I had to do after replacing the cat and various other work attempting to clear the code. Only the front sensor triggers the code.

User avatar
kamesama980
Scoobytruck Master
Posts: 295
Joined: Mon Feb 29, 2016 6:54 am

Re: 03 Baja exaust problems

Post by kamesama980 » Mon May 13, 2019 12:56 pm

What code are you actually getting?

If it's P0420: sorry to bust your bubble airborneguy, but P0420 uses both sensors and you space out the rear sensor. P0420 is set (this is the much simplified method) by the ECM deliberately running the engine lean (as reported by the front sensor) till the cat's full of O2 (as reported by the rear sensor), then runs rich (per the front sensor) and sees how long it takes for the O2 stored up in the cat to be depleted (by the rear sensor reading rich as well). you get around it with a spacer on the rear sensor because the spacer slows down the sensor's response. In the first stage it doesn't matter because it isn't measured. When the second stage happens, the delayed response makes the ECM think the cat's doing better than it is.
-Russell
"You don't get to judge me for how I fix what you break"
03 sport 5mt
05 turbo 5mt vf39 and other STI bits, 3" turbo-back

Airborneguy
Scoobytruck Contributer
Posts: 40
Joined: Thu Feb 22, 2018 6:21 pm

Re: 03 Baja exaust problems

Post by Airborneguy » Mon May 13, 2019 7:51 pm

I was getting 420 right away after every “fix” and reset we tried until I spaced the front sensor. Hasn’t happened again since. I’m not saying you’re wrong, but if that worked for me, what do you think was causing my 420 to trip? You might be able to ID my problem better. It’s been months without the code now after months of it constantly being on regardless of what we tried.

User avatar
kamesama980
Scoobytruck Master
Posts: 295
Joined: Mon Feb 29, 2016 6:54 am

Re: 03 Baja exaust problems

Post by kamesama980 » Fri Jun 14, 2019 8:45 am

Airborneguy wrote:
Mon May 13, 2019 7:51 pm
I was getting 420 right away after every “fix” and reset we tried until I spaced the front sensor. Hasn’t happened again since. I’m not saying you’re wrong, but if that worked for me, what do you think was causing my 420 to trip? You might be able to ID my problem better. It’s been months without the code now after months of it constantly being on regardless of what we tried.
The same thing causes P0420, the difference is the method of the fix. I would guess that delaying the front signal caused the engine to lengthen the rich/lean cycle giving the cat a little boost in the test vs skewing the results by spacing the rear sensor. Different method, different effect, similar result. You cheated on the test rather than lying about the results.

I would hesitate to mess with the front O2 sensor also because that's the one that sets fuel trims.
-Russell
"You don't get to judge me for how I fix what you break"
03 sport 5mt
05 turbo 5mt vf39 and other STI bits, 3" turbo-back

Post Reply