Secondary O2's - Check Engine Light - Solution?

[exnoodle]

I have a check engine light from the secondary O2's. I bore scoped the Cat's and saw that the front side of the honey comb is good, but backside is in rough shape.

Car already has straight zinc plated defouler installed. Thinking about picking up angled ones instead, hoping for a better result. Anyone have any experience with this?

Angled defoulers I was looking at: http://www.bigdaddiesgarage.com/angled-cel-fix.html
Or
https://www.privatelabelmfg.com/prod...QaAvbdEALw_wcB

Car's specs: 2008 E93 M3, 6 speed MT, No Mods, 113K.

[exVtekGuy]

why not just get used low miles oem xpipe? Around $400 is the going rate in the market.

[exnoodle]

I am finding them hard to find & close to me (Albany, NY). Did find a place in NJ that may have one (MParts world wide), which I am trying to get down to, but not easy to align taking a day off to drive 4 hrs or so (round trip).

Found just the Cats on Ebay, but they were cut, and they wanted $500. I have a MIG welder, and could weld it, but figured $500 felt steep.

I also found these, unsure if anyone has had any success: https://www.turnermotorsport.com/p-5...ensor-adaptor/

Any other thoughts and or experience from the good folks on the forum?

[bmwpower603]

Don’t buy new cats

This stuff :



It works. I had a check engine light due to the voltage difference on o2 sensors being to far apart.

When the tank is on empty, put 1 bottle of cataclean in and fill to a quarter tank.

Repeat with another bottle once that tank is empty.

[ciges]

Only one that works is O2 spacer with catalyst inside,none of those empty angled tubes or spacers work.I have test pipes and stage 2 tune ,no cel and passed smog check with 1 unset monitor.They are cheap on eBay;
https://www.ebay.com/itm/CEL-Check-E...IAAOSwyXFaqwkR

[pbonsalb]

The best mini cat 02 modifiers are probably the fabspeed. Also expensive.

[exnoodle]

ciges - Thank you, purchasing a pair tonight.

[pbonsalb]

Those ebay minicats likely won’t work on a catless xpipe. They might work if you still have the rear cats (I know that does not make sense but retaining the rear cats seems to help) or if your front cats are slightly damaged and less effective. Same goes for spacers even the kind with restrictors.

If you have all other monitors ready, you can miss one. A good scan tool shows the readiness monitors using the generic obd2 setting.

[exnoodle]

I have an OEM set up. The front cats are damaged. The front looks good, but the back side looks blown out.

I will try to get my bore scope down there again and take pics and post.

Parts should arrive tonight, will keep you guys posted.

[bmwpower603]

Is the honey comb full of peanut butter?

Or is it actually falling apart?

Or both?

Run a test plan on ISTA in either case.

If clogged with shit, use the cata clean as I mentioned before. It will save you from needing to buy an exhaust.

[exnoodle]

See borescope of the cat's, driver and passenger side. This is looking from the post cat sensors towards the pre cat sensors. Unsure what the red stuff is on the drivers side.

I dont have the pics looking from the pre-cat sensors, but when i looked, towards the post cats, the honey comb is full and undamaged. I did move the camera up stream, through the hole, to take pictures of the back side of the honey comb that is in tact.

I hope this makes sense.

The mini cats came in today, just installed them. Will need to wait until tomorrow to put it through the cycle to see if the Cat readiness passes. Will keep you guys posted.

https://drive.google.com/file/d/1-I_...ew?usp=sharing
https://drive.google.com/file/d/10KK...ew?usp=sharing
https://drive.google.com/file/d/1-vy...ew?usp=sharing
https://drive.google.com/file/d/1124...ew?usp=sharing
https://drive.google.com/file/d/106j...ew?usp=sharing
https://drive.google.com/file/d/113W...ew?usp=sharing
https://drive.google.com/file/d/1-qm...ew?usp=sharing
https://drive.google.com/file/d/1-cM...ew?usp=sharing
https://drive.google.com/file/d/1-jy...ew?usp=sharing
https://drive.google.com/file/d/1-PU...ew?usp=sharing
https://drive.google.com/file/d/10NC...ew?usp=sharing
https://drive.google.com/file/d/1-r1...ew?usp=sharing
https://drive.google.com/file/d/10nU...ew?usp=sharing
https://drive.google.com/file/d/1-WP...ew?usp=sharing
https://drive.google.com/file/d/10hs...ew?usp=sharing
https://drive.google.com/file/d/1-hd...ew?usp=sharing
https://drive.google.com/file/d/10sB...ew?usp=sharing
https://drive.google.com/file/d/1-Fa...ew?usp=sharing
https://drive.google.com/file/d/1-pa...ew?usp=sharing
https://drive.google.com/file/d/1-le...ew?usp=sharing
https://drive.google.com/file/d/10p1...ew?usp=sharing
https://drive.google.com/file/d/10Ub...ew?usp=sharing
https://drive.google.com/file/d/10Y-...ew?usp=sharing

May consider getting the Cat cleaner, just to help add some safety margin, really dont want to hear or see the check engine light.

[exnoodle]

ciges - Just passed my inspection, thank you. They worked, will check in after I put some miles on this set up.

[Inglewood]

Picked up a 2010 e90 M3 with AFE test pipes and exhaust as well as a BPM stage II tune. Failed readiness portion of my state OBD emissions test the other day here in WI - car is not throwing CEL or codes currently with the tune, but I did replace throttle actuators and a coil the other week and flashed codes after work completed.

Wondering if a defouler or extender would even help my cause at this point? The emissions guy said to just go drive a few hundred miles if I just cleared codes after work a week ago - which I've done - but nervous to go back and fail again. He obviously did not know I was catless. My Foxwell OBD scan tool does not (to my knowledge) show readiness?

Any advice is greatly appreciated! Dont want to change out pipes if possible and lose my tune, as I was not the original owner and would have to repurchase according to BPM.

Here are a few of the options that seem legit for a defouler:

http://www.bigdaddiesgarage.com/stra...MaAkyuEALw_wcB

https://www.amazon.com/Vibrant-11619...ustomerReviews

https://www.ebay.com/itm/CEL-Check-E...IAAOSwyXFaqwkR

[pbonsalb]

Your Foxwell tool should show readiness, at least my NT510 does. Use generic obd2 not bmw specific. Look for I/M readiness. Don’t go back to inspection place until you have only 1 not ready. You are allowed one.

If after a few days or more of varied driving you are still showing 2 or more not ready, you must fix one. If it is for the cats, you will have to swap cats back in or try one of the minicat 02 modifiers and there is no guarantee the modifiers will work. They work for some people and not for others and of course they are nonreturnable.

I doubt the vibrant restrictors will work. I’d try one of the minicats. I think the fabspeed are the best but also the most money and still no guarantees.

Having the rear 02 simulated in the tune is best but illegal so few tuners will do it for you

[exnoodle]

The ebay option worked for me. Very interested to see for how long