GOLFMK8
GOLFMK7
GOLFMK6
GOLFMKV

CBFA O2 Spacer

iiCaptain

New member
Ok I have done a lot of research and looked at past forums, and figured I might ask the question once again because most of the helpful ones are a decade old. With cobb's new green speed update new tunes no longer turn off the check engine light for P0420. Well I got a new tune and my check engine light is on. I would have gone apr but they discontinued it, and my only other options are uni/IE. UM is not near me nor are any other tunes that I am aware of. The only reason I haven't gone with uni/IE is because I like having the accessport to swap tunes and look at numbers. Uni doesn't have a pop tune and IE's pop tune is extremely annoying, I like the way my stratified pop tune is now.
So basically I would really prefer to keep the accessport but if it is too hard to turn off the CEL I might as well go a different route. Anyways from what I've read it is really hard to trick the CBFA because of the second O2 sensor. I am thinking if I want to try I can get two adjustable O2 spacers and play with it until it works. Slightly space the first one and the space the second one even more? One issue is finding O2 spacers. They're everywhere, but they're a lot more expensive than I thought they would be. And not a lot are adjustable/cheap, really hoping to not spend $100 on spacers.
Also I don't have emissions where I am, is there a way to just keep it in a constant state of not ready? I'm still confused on how this works but if possible that would be a nice solution. Just trying to keep the light off, don't care about being able to pass emissions.

Anyways that's the situation, let me know what you think the best route to take is and if you know how to get that light to stay off without electrical tape or pulling the physical light out of the dash lmk. Also if you know of any O2 spacers please send the link.
 

iiCaptain

New member
there’s posts describing exactly what you say. 2 adjustable spacers using different size openings.

https://www.emdauto.com/products/ox...ith-adjustable-inserts?variant=42569634316547

Can find them even cheaper from China.
Yeah that's what I've gathered. Unfortunately I tried using some spacers from china and my o2 sensor didn't fit, as it didn't go deep enough. I need 90 degree or 45 degree spacers because my o2 sensors barely fit in the tunnel as is, unless I could lay them level but even then I don't think that would work. Just going to keep looking for spacers that work.
 

JOHNDERS2586

Ready to race!
Found a rip off J style spacer online for about 35$ from Jcarparts. OBD2 Vehicle M18X1.5 J Style O2 Oxygen Sensor Angled Extender Spacer Kit Generic × 1. I put it on with middle insert post cat . Haven't had a P0420 code since. Aftermarket Catted DP on CBFA. Custom Cobb tuned W KO4.
 

iiCaptain

New member
Figured I would follow up here with what I did for anyone coming across this in the future. I tried out one J style spacer on the last O2 sensor with both medium and small inserts and they both worked well except for scenarios where I was cruising with the car at 1500-2500 rpm for extended periods of time. I finally got a second spacer and put it on the middle O2 sensor with the large insert. I've since driven the road and speeds that it used to set off a CEL and it now does not. Will update if this fails but so far so good.
 

Attachments

  • 20230531_173433.jpg
    20230531_173433.jpg
    1.5 MB · Views: 52

nomz_mk6

Ready to race!
hey, any updates on your end? this thread inspired me to buy these spacers. I installed them yesterday, here's some notes:

Background: CBFA motor, ARM catted downpipe. Trying to pass NYS inspection/emissions
-initially was on a "stage 2" stratified tune but I reverted back to "stage 1" for the time being.. I believe that stage 2 would prevent catalyst monitor to be ready
-after 50 miles on stage 1 without spacers, I'd get a P0420 CEL.. all monitors set to ready though
-yesterday, installed both spacers. pre cat got the medium jet, post cat got the small jet. Engine was already warm.. cleared the CEL and went for a cruise
-after a 20 mile city drive in traffic with some highway sprinkled in, no CEL yet + all readiness monitors set besides SAI and EVAP
-notably, catalyst was set to ready after just 10ish miles


IMO, and not trying to jinx this, it seems the spacers have helped. hopefully the SAI + EVAP monitors will go away after a cold start and idle. will update once I pass inspection
 

JOHNDERS2586

Ready to race!
For me personally, I had run 1 J spacer mid setting post cat for about 10k miles then I started getting codes again.. ran through about every configuration of J spacers on both post an pre cat with no luck 2 J spacers. Ordered a 45 and a straight spacer off Temu.. Straight spacer on the pre and 45 on the post cat. Finally back to no cel for a few hundred miles now. Fingers crossed..KO4 with catted DP CBFA
 

Alpinee30

Go Kart Newbie
I suggest trying a quality catted 90 like one from Racing Dynamics or fabspeed . I've got about 17k on my setup since COBB went green
 

iiCaptain

New member
No P0420, but I've gotten a couple other codes. Moved down to Memphis for the summer and on the 10 hour drive down P013A set off, and then just today P2271 and P2096 set off. Never had these ones before so I'm thinking it could be a number of simple things like O2 spacer orientation. I would start by checking for an exhaust leak but since I don't have a jack and these codes rarely set off I'll fix it when I get back home in August. Till then I'm just going to clear them and record how often they come up. Car runs fine except for it's so damn hot it's just pulling timing so I'm not pushing the car at all, just commuting on some of the worst roads I've ever seen.

Btw I am stratified stage 2 and no it doesn't prevent the catalyst monitor from being ready. Only if you have a stratified tune from pre-april 2022 then it will keep CEL off.

Depending on how I feel after this summer might just get a catted DP or switch tuners. Will see if I care to mess with this for much longer, no emissions here so in no rush.
 

nomz_mk6

Ready to race!
Passed inspection! The J spacers were the trick. Could’ve been overkill but it worked
 

Attachments

  • AD980328-3052-4FCF-B72E-02B3B39AB739.jpeg
    AD980328-3052-4FCF-B72E-02B3B39AB739.jpeg
    341.9 KB · Views: 36
Top