JamesD89

2007 with Flashpro
No cat (Gernpipe), both O2 sensors work
90 degree, ~4in long O2 senor bung, no CEL

Over the last week I've been struggling to get the catalyst readiness monitor to reset so I can get my car smogged. I've followed the procedure in the owner's manual as well the advice in this thread: https://www.s2ki.com/forums/s2000-en...shpro-1094009/. At this point I think my issues are either:

1. Not having a cat, or the O2 bung is too long. I'd like to avoid tracking down and installing an OEM exhaust and cat since my shop doesn't do a visual check on OBD2 cars.
2. I'm not following the OEM readiness reset procedures correctly.

#1: Can the monitor be reset without a cat? I assumed I would be fine with a functioning secondary O2 and no CEL.
#2: how closely do the OEM procedures have to be followed? I have to drive my car for approximately 10 minutes before I can get anywhere that will allow me to maintain a constant speed of 50-60mph for 20+ minutes. I've put about 300 hundred miles on the car (including one 180 mile round trip) since reflashing the ECU and installing the secondary O2.

Kenny_Stang

If you don't have a catalytic converter, the catalyst monitor will never set, even if the catalytic converter is marginal, it can take a while to reset. I keep my stock catalytic converter for just this reason, when I need to get car inspected I swap it back on and flash back to my tune that has the secondary 02 enabled. Even then it takes me about a week and ~200 miles to get all the monitors to set.

JamesD89

Really? Looks like I need to track down an OEM exhaust then.

I'm wondering why that is the case though. My secondary O2 is enabled, functioning, and there's no CEL. What's preventing the catalyst monitor from setting?

Kenny_Stang

The catalyst monitor uses the secondary 02 sensor to detect the health of the catalytic converter, if the catalytic converter is not present, the catalyst monitor will never set.

JamesD89

I thought that was why people ran the O2 bungs? If the cat isn't present or functioning you'd get a CEL.

Not arguing with you, really just trying to figure out how all this work

flanders

Yes an O2 bung fools the O2 sensor that the "cat" is working, otherwise you would get a CEL.
Not sure why you don't get the catalyst monitor set though, maybe some other parameters is needed as well.

Btw the Gernpipe does have a hfc or have you removed it?
I know it sits after the secondary O2 sensor though so it wont matter in this case.

Kenny_Stang

The issue is that with the 06+ ECU, the "bung" method does not always work. The 06+ ECU is more advanced than the previous computers, and unless you disable the secondary o2 sensor, you will eventually get a check engine light for the catalyst. Here are some threads that cover this issue:

https://www.s2ki.com/forums/s2000-un...w-ap2-1137838/

https://www.s2ki.com/forums/s2000-un...t-pipe-564459/

https://www.s2ki.com/forums/s2000-un...roblem-931396/

JamesD89

I still have the HFC that's near the rear axle, and I wouldn't be surprised if the car passed a tailpipe test with it. That alone sadly doesn't fly in CA.

Thanks

After putting another 100ish miles on the car last night I got a CEL for the secondary O2 so you're right