Found Out My '04 Has Had A Pciii With No O2 Sensor Eliminators Since I Bought It - What Have I Done, And What Do I Do?

[WalkThisWhey]

Have had my 04 for a few years now, and I knew it came with a PCIII on it. As time has gone on, I realized the bike wasn't really abused, but it wasn't modified with a job done "right" - case in point, they installed the Power Commander III, and that's it.

No PAIR block off, so the exhaust would pop (fixed now), and now this - no O2 sensor elimination. The thing is, I know this would cause some sort of Check Engine light to come on, and since I have owned the bike it has never given me that light.

What it has given me is a very, very rich exhaust smell the whole time, and I figured this was because of the PCIII. I am beginning to wonder if the O2 sensors being in place are causing an issue here.

Anyhow, now that I've been riding around and track daying like this for a few years, are there other issues I should look for in addition to putting some O2 sensor eliminators on?

[CornerCarver]

You can spend $2 on some resistors and they will do the same as the O2 eliminators.

I would put some resistors in and then spend some money for a proper dyno tune.

If it didn't have O2 eliminators then it probably just has a standard map or a map that someone else downloaded from the interwebs.

[Cogswell]

The resistors are 330 ohm - anything 1/2 watt + should do. Just jump the appropriate pins in the connectors and tape them up. If you've been smelling fuel, that's the cause of the popping on decel - the pair system is only adding air that ignites the excess fuel. Disabling the PAIR has only masked the symptom, not corrected the problem. My '08 has the PAIR system in place and has no unwanted behavior on deceleration. You can search P.C.'s website for maps and alternatively there are some in the downloads section that should get you close. A dyno tune can definitely refine it and smooth out any rough spots.

Since it's been running rich, it's worthwhile inspecting the plugs for fouling or carbon. Highly excessive fuel can end up burning in the cat. That happened to someone here running a "Booster Plug" - it ran so rich the cat melted. If the dyno run shows everything's good but it's down on power, check the cat for melted substrate.

[WalkThisWhey]

The resistors are 330 ohm - anything 1/2 watt + should do. Just jump the appropriate pins in the connectors and tape them up. If you've been smelling fuel, that's the cause of the popping on decel - the pair system is only adding air that ignites the excess fuel. Disabling the PAIR has only masked the symptom, not corrected the problem. My '08 has the PAIR system in place and has no unwanted behavior on deceleration. You can search P.C.'s website for maps and alternatively there are some in the downloads section that should get you close. A dyno tune can definitely refine it and smooth out any rough spots.

Since it's been running rich, it's worthwhile inspecting the plugs for fouling or carbon. Highly excessive fuel can end up burning in the cat. That happened to someone here running a "Booster Plug" - it ran so rich the cat melted. If the dyno run shows everything's good but it's down on power, check the cat for melted substrate.

This is awesome, thanks for the direction here. Unfortunately, the bike is tucked away for winter so the tune will have to wait. I will be giving the resistors a shot.

[WalkThisWhey]

So I wanted to follow up on this thread - I ended up putting the resisters on, got no FI light (tested without them, and it came on, so they're working).  Good to go!

Personally I don't feel any difference as if it's smoother, and the exhaust still stinks.  I am wondering if the lack of eliminators toasted the cat, or if the previous owner just straight up gutted the cut?  Outside of a catback Two Brother system, the cat looks to physically be there so I'm not sure how to check outside of removing the cat back exhaust.