VitalSyntax

I just bought a 2006 Touring 350z and am having a HELL of a time trying to get it through emissions. The car has Strup headers, high flow cats (not sure what brand/couldn't find any markings), and a fast intentions cat back exhaust.

The high flow cats are throwing the P2A03 02 sensor range bank 2 sensor 1 error (as expected). I've already tried extending the 02 sensors AND adding steel wool and have reset the ECU and gone through the required drive sequences (to get it out of learning/readiness state), but the CEL came back on after about 60 miles.

I bought some OEM cats off ebay hoping I could swap out the high flow cats, but the OEM cats are too short. I'm not sure if this is because the Strup headers are shorter to make up for the extra length of the HFC or if I'm missing something...

Here is a photo of the high flow cats (on the right) and the OEM cats on the left:
http://imgur.com/a/4USlb

And yes I KNOW these are HR OEM cats not DE cats (side by side here: http://s1219.photobucket.com/user/3p...b4d06.jpg.html). I didn't know there was a difference between the CATS on the HR vs the DE when I bought them. BUT the DE cats are even shorter, so either way they aren't going to fit without modifications...

So, I guess my question is: should I attempt to modify the HR cats (have to replace flange that connects to headers and extend the cats by 1") OR should I just go back to stock headers and stock DE cats?

I'm guessing even if I went through the trouble of modifying the HR Cats to fit that I'd still end up with an 02 sensor error.

TDLR:
Will the HR cats throw a CEL on a DE engine? Is there a good aftermarket (non-high flow) cat for the DE 350z that won't throw a CEL light?

travlee

iTrader: (8)

the hr cats wont mount to the de headers. the best bet would to have the car tuned to fix the lean issue

VitalSyntax

Thank for the reply. Your right the HR cats won't mount to the DE headers. I'm dumb for buying them in the first place, I should have done my research. Oh well, I can probably sell them.

I figured out that bank 2 sensor 1 is for the drivers side pre cat o2 sensor (I think it is part of the manifold). So my high flow cats aren't currently the issue for the P2A03 error. It is likely a leak in the manifold, a leak in the intake, or need to clean/replace the mass airflow sensor.

I already replaced the o2 sensor, but the light came back on for the 3rd time. I'm going to have the manifold/intake/mass airflow sensor looked at in a few days.

I purchased the car 3 weeks ago and still haven't gotten through emission...

VitalSyntax

Another update. Shop (Atomic Race Works in Spokane WA) did a exhaust manifold leak test and didn't find any major issue. They also took apart the intake tubing, intake manifold (plenum I think), and found a few broken bolts, and a few unclamped lines. I'm guessing the previous owner removed a plenum spacer before he sold me the car and didn't put everything back together properly. (He had 2 other 2006 350z's in his driveway/garage when I bought it from him).

But regardless, after ARW replaced the bolts, replaced the clamps, and cleaned the mass airflow sensor the CEL came back on after ~40 miles.

Our next ideas are to replace the mass airflow sensor and possibly swap the 02 sensors from side to side. Also we might try installing an ECU flash from Osiris to remove the code. BUT my main goal is to get the car through emissions so I can actually drive the damn thing.

Anyone know for sure if the Osiris ECU flash sets the ECU in "readiness"/"learning" mode? Because that would be detected by emissions, right? Are there any ECU options that can remove the engine code but not be detected by emissions?

travlee

iTrader: (8)

It sets them to not ready, in texas you can have 2 not ready and pass

VitalSyntax

Seems like WA doesn't allow any "not ready" sensors: http://www.emissiontestwa.com/e/OBDReadiness.aspx

VitalSyntax

Guess my next step is to try and replace the mass airflow sensor and cross my fingers. If that doesn't work I'm out of ideas. Maybe go back to stock headers + stock cats.

coletrickle74

iTrader: (1)

You can disable the codes and pass emissions just fine. I just did it for the 2nd time last week. Although Uprev isn't the cheapest solution.

VitalSyntax

Oh really? Are you using uprev? Do you have any suppressed codes? Is your ECU in a "not ready" state on any of the codes on an OBD II scan? I though emissions would detect the "not ready" state that the ECU is put into and require you to keep driving until the drive cycle is compete.

coletrickle74

iTrader: (1)

Everything in the ECU is ready. I just disabled or "suppressed" the codes in uprev. I drove it a couple days to work to complete the drive cycle, then took it in for testing. I did the same thing last year when I put test pipes on

VitalSyntax

Final update:

We called Uprev and they said suppressing the code would set the car in N/A or Not Ready state, which would not pass emissions in WA. Next we tried swapping the mass airflow sensor but that didn't work either. So at this point we've tried all of the easy fixes and none of them worked. My next option was to go back to the stock headers and stock cats which would cost me quite a bit, I'd lose power, and it might not even fix the issue.

I ended up registering the car at a friends house outside of Spokane where emissions are not required. I'm keeping the car in his garage often anyway and will leave it there during the summer since he lives right next to the autocross venue in Deer Park.

I'm just happy I'm able to drive the car now, for a moment I was worried I'd have to sell it and find a new car. I will probably setup Uprev engine management soon to suppress the code since it doesn't have any impact on performance and I've tried everything to fix it.

Thanks for your help guys!