Back in March, my car didn't pass Virginia emissions because not enough of the monitors were showing ready/complete. IIRC, I had 4/5 needed tests pass but O2 sensors were reporting not supported and that's what got me. I have cams, JBA long tube headers, & hi-flow cats which were installed in 2016 but I'd never had a problem passing emissions before. But I think VA has gotten more stringent about it apparently because my shop says I'm not their only customer with this problem all of a sudden. I did a lot of searching on this across a couple different forums and the most common answers are:
1) Your rear O2's are turned off in the tune so it doesn't throw codes
2) You need to do a proper driving cycle (10 min highway, 20 min around town) so the computer can complete its tests
3) The O2's are blowing cold (too much airflow so they can't come up to temp in time) - try having your tuner increase the amount of time for the O2's to warm up before testing
4) the O2's might not have enough of a output range to read properly - try using OEM NTK O2 sensors which have a wider range than Bosch
So far
- I cleared the computer and did a driving cycle, ~ 75 mi (no dice)
- Changed my mufflers back to stock because the only mod I'd done since the last time I passed emissions was a set of Borla touring mufflers which are more free flowing than stock. So, even though the cats are probably the restriction point in the exhaust I figured why not, mufflers aren't hard to do. Cleared the computer, another driving cycle (no dice)
- replaced the O2 sensors with NTK's, pulled the battery for 30 min, did another driving cycle ~45 mi (no dice)
- Contacted the shop back in March, said the O2's aren't turned off and they'd check with SCT. Didn't hear anything back for a few weeks, so while I was doing another driving cycle yesterday I stopped by the shop they'd have to look at the tune again to be sure but most likely the rear O2's ARE actually turned off. He also said SCT pretty much said they wouldn't help because as you guys might remember from the news a couple years ago they got slapped pretty hard by the EPA for helping customers circumvent emissions.
I also mentioned to the shop that I drove by one of those RapidPass roadside emissions boxes and failed, so they're fairly certain that regardless of what the computer says, what's coming out the tailpipe isn't in legal limits. They suggested Kooks Green Cats since they're EPA certified and would actually bring my emissions down so I won't have to worry about this anymore.
So, a set of green cats look like they're in my future. Anyone have any thoughts on them?
Kooks does make a green catted H-pipe for long tubes but it has ball & socket flanges, vs the JBA one I have has a slip-on joint. So it looks like I'll either have to get the JBA hi-flow cats cut out and the Kooks cats welded in, or switch the whole cat-forward system to Kooks.
I've never been horribly impressed with the quality of the JBA system (the ceramic is flaking off already) and the Kooks looks top notch, but we're talking $3k ($1400 for the headers (w/ ceramic coating) $1200 for the h-pipe, + tax) not even counting installation. Or roughly $800 for just the cats plus a couple hundred for labor.
1) Your rear O2's are turned off in the tune so it doesn't throw codes
2) You need to do a proper driving cycle (10 min highway, 20 min around town) so the computer can complete its tests
3) The O2's are blowing cold (too much airflow so they can't come up to temp in time) - try having your tuner increase the amount of time for the O2's to warm up before testing
4) the O2's might not have enough of a output range to read properly - try using OEM NTK O2 sensors which have a wider range than Bosch
So far
- I cleared the computer and did a driving cycle, ~ 75 mi (no dice)
- Changed my mufflers back to stock because the only mod I'd done since the last time I passed emissions was a set of Borla touring mufflers which are more free flowing than stock. So, even though the cats are probably the restriction point in the exhaust I figured why not, mufflers aren't hard to do. Cleared the computer, another driving cycle (no dice)
- replaced the O2 sensors with NTK's, pulled the battery for 30 min, did another driving cycle ~45 mi (no dice)
- Contacted the shop back in March, said the O2's aren't turned off and they'd check with SCT. Didn't hear anything back for a few weeks, so while I was doing another driving cycle yesterday I stopped by the shop they'd have to look at the tune again to be sure but most likely the rear O2's ARE actually turned off. He also said SCT pretty much said they wouldn't help because as you guys might remember from the news a couple years ago they got slapped pretty hard by the EPA for helping customers circumvent emissions.
I also mentioned to the shop that I drove by one of those RapidPass roadside emissions boxes and failed, so they're fairly certain that regardless of what the computer says, what's coming out the tailpipe isn't in legal limits. They suggested Kooks Green Cats since they're EPA certified and would actually bring my emissions down so I won't have to worry about this anymore.
So, a set of green cats look like they're in my future. Anyone have any thoughts on them?
Kooks does make a green catted H-pipe for long tubes but it has ball & socket flanges, vs the JBA one I have has a slip-on joint. So it looks like I'll either have to get the JBA hi-flow cats cut out and the Kooks cats welded in, or switch the whole cat-forward system to Kooks.
I've never been horribly impressed with the quality of the JBA system (the ceramic is flaking off already) and the Kooks looks top notch, but we're talking $3k ($1400 for the headers (w/ ceramic coating) $1200 for the h-pipe, + tax) not even counting installation. Or roughly $800 for just the cats plus a couple hundred for labor.