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Can't pass emissions..

7014 Views 8 Replies 6 Participants Last post by  XJman
I have an 02 wrx and I live in PA and can't pass OBD emissions test because My 02 sensors aren't ready along with OBD-I/M check not ready. The only thing I can thing of is that I have a catless downpipe and maybe that making me not pass, I have an AP and I'm on a stage2 map. My AP throws the code P0037 (heated oxygen sensor) I'm somewhat new to this, I was told by a friend that all I would need to do is put a downpipe with cat and I should pass it. Could that be the reason it is showing "not ready"?
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Your rear O2 sensor is bad. They have a heater element, and yours is having trouble. Replace the O2 sensor, or disable the DTC.
Doesn't matter what the rear O2 is doing having no catalytic converter is a fail for sure

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You can pass catless...IF they forget to look. Here, all it is is an OBD2 check, and a gas cap check for anything newer than a 99. It just all depends on how exactly they do the inspections
Better safe than sorry though. Fix the o2 sensor, put the cat back on, and go through your drive cycle...should be alright as long as the monitors show ready
You can pass catless...IF they forget to look. Here, all it is is an OBD2 check, and a gas cap check for anything newer than a 99. It just all depends on how exactly they do the inspections

Definitely depends on where you live.. if they put the car on a dyno with a I/M240 or ASM 4-Gas analyzer test you'll definitely fail, whether they look or not.
Definitely depends on where you live.. if they put the car on a dyno with a I/M240 or ASM 4-Gas analyzer test you'll definitely fail, whether they look or not.
By chance, would turning off the code have any effect on the monitor being ready?
By chance, would turning off the code have any effect on the monitor being ready?

I'm not positive, but I think a DTC that has been turned off won't show ready. The only time I remember having to deal with it I used Rom Raider to force readiness on all sensors before I went in for inspection. Usually you only have to have a certain number of sensors showing ready to pass but I do not know how many.
In PA all they do is an ODB2 scan and gas cap check. On vehicles older than 01, 2 monitors can report not ready. 02 and newer can have 1 monitor not ready. When you clear codes, all monitors are reset and will need a complete drive cycle to show ready. Unless you have a tuner or yourself through open source set the monitors for forced readiness. With forced readiness, just clear codes before heading for inspection and you'll pass with no problem. That's how mine passed with no cats. If the CEL is on before they hook up though it will fail. After code reset I get about 100-150 miles before it comes back. So that's plenty of time to get the stickers ?
Or you could forgo all of that and just use a high flow cats and be done with it.



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