Catted O2 spacer recommendations

[Good2Go]

Hello all,

I’m going to have to go in for emissions soon and my o2 sensors are throwing P0430/20 codes due to my stainless works downpipes w/ Gearhead AO tune. I got a recommendation from someone trusted in the community for these catted o2 sensor spacers (as well as recommendation that the spacers would in fact set the I/M monitor to ready): https://www.racdyn-usa.com/PROD/130+10+10+013.html

Before I drop the money on them I just wanted to see if anybody else had luck with this strategy, and to confirm whether or not I should go with straight or 90 degree ones. Also i should add I’m not keeping these on forever, just putting them on to pass emissions and then removing them later on

 

[luigisho]

I have heard of O2 spacers to pass emissions. No personal experience with them. Post back with results if you use them. ALso if the sensor is the issue and not the cat then maybe the spacer won't work?

 

[Good2Go]

I have heard of O2 spacers to pass emissions. No personal experience with them. Post back with results if you use them. Also if the sensor is the issue and not the cat then maybe the spacer won't work?

just ordered them, I'll let you know if they worked towards the end of the month. I highly doubt its the o2 sensors since the rear ones rarely fail and multiple people on this forum with the same stainless works downpipes have this issue. I'm just hoping the gearhead tune doesn't keep the I/M set to "not ready" once I have no codes, but we'll see. I've been told by them if there's no codes it should set it to ready.

 

[Mahu24]

Get the 90° ones, gives you more flexibility to keep the O2 sensors up and out of the way

 

[Good2Go]

Spacers are on. Cleared the codes, did about 68 miles today, cleared the codes again, still there. Gonna go another few days and see if they go away since I know the ECU needs time to adapt

 

[BradM]

I've used O2 extenders with success on several vehicles with weak/failed cats (Toyota, BMW). I've avoided using the ones with a mini catalyst as I don't think it would never get hot enough to ignite. The goal of an extender is to pull the O2 sensor out of the exhaust stream far enough to where the fluctuations from the (failed) cat test are minimized (kept in range) but not far enough to produce no fluctuations (measuring out of range). I wouldn't give up on the extenders yet. See if you can remove the mini cat material or get ones that are fully open. You don't need to wait very long for the cat test to be completed, you'll know after clearing the codes and completing one drive cycle.

 

[BradM]

Here you'll find a graph showing good/bad cat waveform.

Bad O2 Sensor or Cat Problem?

Here’s what the O2 sensor signals should look like. Tester

community.cartalk.com

 

[Mahu24]

These are the ones I used with my catless downpipes

Amazon.ca

 

[Good2Go]

just datalogged it, my rears are hovering steady between .5 and .6, so I'd say they're doing good and its most likely just a matter of waiting for the I/M's to flip to ready and for the codes to go away. this pic shows my readings. they're fluctuating but not brutally

Here you'll find a graph showing good/bad cat waveform.

Bad O2 Sensor or Cat Problem?

Here’s what the O2 sensor signals should look like. Tester

community.cartalk.com

 

[BradM]

just datalogged it, my rears are hovering steady between .5 and .6, so I'd say they're doing good and its most likely just a matter of waiting for the I/M's to flip to ready and for the codes to go away. this pic shows my readings. they're fluctuating but not brutally View attachment 94746

It looks like its tracking the upstream sensor too much IMHO (should be much smoother) but let us know if it clears.

 

[Good2Go]

It looks like its tracking the upstream sensor too much IMHO (should be much smoother) but let us know if it clears.

Are you sure? The guide you sent showed the upstreams bouncing between .1 and 1.25, these are only bouncing between 0.5 and 0.6, less than a tenth of that upstream range

 

[BradM]

My bad. I thought you were comparing upstream and downstream. What does that data look like?

 

[Good2Go]

My bad. I thought you were comparing upstream and downstream. What does that data look like?

Have to take another datalog, my livelink said the field I selected for the upstream were invalid and I didn’t have time to enable the actual one for a second run

 

[BradM]

Get the car to 50mph or higher for 5-10 minutes so it will trigger the test. It likes to see a steady state so it can richen the mixture and see how the cat responds.

 

[Good2Go]

Get the car to 50mph or higher for 5-10 minutes so it will trigger the test. It likes to see a steady state so it can richen the mixture and see how the cat responds.

I did like 20 minutes today at like 65-70 and the codes are still there. Still haven’t been able to find the upstream field in livelink. Sometime tomorrow I might use my SCT to clear the codes instead of my FIXD plugin since the SCT resets the codes a lot more thoroughly. Do you have any sho datalogs where you clocked the upstream sensor voltage?

 

[BradM]

I don't have any data logs for you. The codes should have cleared by now. Did you remove the mini cat material from the extender or just leave them as-is?

 

[Good2Go]

I don't have any data logs for you. The codes should have cleared by now. Did you remove the mini cat material from the extender or just leave them as-is?

I didn’t remove the mini cat material, I really don’t have time to at this point, I barely had time to put them on. **** I don’t even think I could get the cat material out without making them useless. Worst case scenario Ill probably end up just taking my tune and cats off sometime in the fall (assuming the state doesn’t come down on me since my extension expired in June and they gave me a month extension to the end of July after failing the first time)

 

[Good2Go]

Ok, over a week later, about 300 miles or so and the codes are still there. Gonna have to conclude that these things don’t work, lol