P0430 and P0420 Catalyst System Efficiency Below Threshold bank 1&2

[Stück]

Be humble? I'm here to help those that will listen. Be the guy that doesn't perpetuate misinformation.

[kswist24]

I work at an auto shop and sometimes when customers with upgraded cars have cat codes we use the spark plug foulers. It works 80% of the time. I haven't done one on a bimmer but on merks VW and audis it's been pretty good. Japanese not so good. So on my part give it a shot. It's Guna cost you about 25 for a dorman piece set and a little labor time to drill it out.
Like people have posted before. BE CAREFUL when your boring out the fouler. Tight fit is better.

[bcain79]

Be humble? I'm here to help those that will listen. Be the guy that doesn't perpetuate misinformation.

I have been battling the P0430 code for a year now. I am trying this fouler trick this week! I will report my findings.

THANK YOU!!!

[bcain79]

Okay, I just finished putting the fouler in bank 2 ... We'll see if that dang p0430 code comes back! I'll keep you updated. It usually pops on every other day or so ....

I hope this works!

[bcain79]

Okay, I just finished putting the fouler in bank 2 ... We'll see if that dang p0430 code comes back! I'll keep you updated. It usually pops on every other day or so ....

I hope this works!

So, the check engine light stayed off - BUT, my fuel milage dropped from 17 to 14 mpg right after. I took the foulers out today. I would rather get better gas milage and have the CEL on then the other.

[Stück]

You understand the post-cat O2 sensors have nothing to do with engine running variables, nor does the DME look at them for any purpose other than catalytic converter efficiency right? Removing them will do nothing buy waste your time.

I have no idea why your MPG average has dropped, but it is in no way shape or form from the non-foulers.

I will say you guys with automatics really take it in the rear on the MPG figures though... I'm averaging 26.4MPG over the last 900 miles.

[bcain79]

You understand the post-cat O2 sensors have nothing to do with engine running variables, nor does the DME look at them for any purpose other than catalytic converter efficiency right? Removing them will do nothing buy waste your time.

I have no idea why your MPG average has dropped, but it is in no way shape or form from the non-foulers.

I will say you guys with automatics really take it in the rear on the MPG figures though... I'm averaging 26.4MPG over the last 900 miles.

Stuck, I always like your comments - But I can't help question this one. I thought the same thing, but ... My mpg tests dont lie. So whether the post o2's really do anything or not is up for debate; however, if I get better has milage without foulers - ain't going to use them.

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Okay, I know these two pics don't tell the whole picture but it's a start. Yesterday, I reset the miles and drove 14.3 miles with foulers some of it was freeway and my average was 13.8 (I have tested this consistently and always get about 14 mpg - ever since I put in the foulers.) So I took them out and drove to work (5 miles exactly) and my average was 26.1 no freeway but I used cruise control for half of it. I know I need to drive more miles than this to test the theory however, this is a start. Before the foulers I always got 17-18 mpg never 14 - then all the sudden I get 14 mpg - awfully suspect to me. I expect for my average over the next week to go to about 17. (I will test the mpg for the next week or so and report back.)

[Stück]

There isn't much to debate, research the inputs of the MS43 DME. The precat sensors are what the DME monitors to make its mixture adaptations. The post cat sensors are for emissions purposes only, IE verifying the healthy operation of the catalysts.

Drive the exact same route with the exact same throttle inputs both times with and without the non-foulers and you will have reasonably acceptable results. Clearing out the old averages and taking a small sample for the new... really isn't a valid comparison.

[bcain79]

There isn't much to debate, research the inputs of the MS43 DME. The precat sensors are what the DME monitors to make its mixture adaptations. The post cat sensors are for emissions purposes only, IE verifying the healthy operation of the catalysts.

Drive the exact same route with the exact same throttle inputs both times with and without the non-foulers and you will have reasonably acceptable results. Clearing out the old averages and taking a small sample for the new... really isn't a valid comparison.

About the fuel milage, that's what I said. I will do a better analysis and report back.

[bcain79]

Update:

For the last year and a half I have averaged 17-18 mpg. I put foulers in and I drove 100 miles and averaged 14 mpg. I took the foulers out and have now driven 100 miles and am back to my average of 17-18 mpg. People say rear O2's don't do anything, but for some reason in my car they do. Take it for what it's worth.

If anyone is considering putting foulers in, make sure you do some mpg tests before and after - it would be interesting to see what others are finding out.

[Stück]

How old are your pre-cat O2 sensors?

By your logic I should be getting low 30's MPG if I ditch the non-foulers.

Something else is going on here, what it is I'm not sure.

[bcain79]

How old are your pre-cat O2 sensors? By your logic I should be getting low 30's MPG if I ditch the non-foulers. Something else is going on here, what it is I'm not sure.

My pre O2's are about 3 months old (Bosch). I even put in new post O2's. I wish you knew what was wrong with my car ... Lol. I am so frustrated with the p0430 code. I am really resisting putting in new cats. I think I am going to put the fouler back in and do another test. Also, I found that my secondary air pump hose was cracked (11721435456) - (i'm not sure if this would throw my code) do you think that could cause the p0430 code? (My code comes on every 2 or 3 days, I clear it and the cycle repeats). Another question - how many hours should an indy charge to install cats I supply (I was thinking pacesetter ???) I know you stated OEM only, but the pacestters are much more affordable (http://pacesetterexhaust.com/bmw-e39...converter.aspx they're on ebay for $275) Sorry for all the questions - your replies are read, mulled over, and appreciated.

[Stück]

I would say reinstall the non-foulers, reset all adaptations, then make another run of it.

Secondary air system pressure hose can't cause that fault.

Those manifold/cat assemblies look downright awful. Hard to say if they would perform better or worse from a flow standpoint over the original equipment.

[bcain79]

I would say reinstall the non-foulers, reset all adaptations, then make another run of it.

Secondary air system pressure hose can't cause that fault.

Those manifold/cat assemblies look downright awful. Hard to say if they would perform better or worse from a flow standpoint over the original equipment.

I just put in the non-foulers and drove a little bit and didn't see a change, i'll drive it a bit and get back to you on more results. --- You really think the OEM cats would be better?

[Stück]

Better in terms of precious metal content and long term efficiency? Absolutely.

OE cats are worth more for their scrap metal precious metal content than those new ones cost period. You get what you pay for.

Platinum and Palladium (the primary reactive and oxidizing catalysts) are very very expensive.

$1500 and $750 per ounce respectively.

[bcain79]

...

Hi Stuck - So I've drove my car around with a heavy foot and my wife took it to NC (few hundred miles). Fuel mileage appears to have not changed with the foulers. So obviously my previous conclusions were inaccurate. The only thing I can think of is that - My MAF went bad a few days after I put the fouler in the first time, so maybe a bad MAF was changing my gas milage? Anyway, thought I would let you know. But my CEL came back on ... ugh.

[rock mafia]

Cats are on the way out.

Do this:

http://www.energeticforum.com/renewa...n-foulers.html

A single non fouler is sufficient to make the cats very efficient. Two of them will make the DME happy with no cats at all.

Bank 2 lean is most likely part #17 here:
http://www.realoem.com/bmw/showparts...79&hg=11&fg=40

The vacuum cap dryrots, splits, and then causes bank 2 to go lean. Order and replace.

I did both of these and changed the o ring on the disa valve, my CEL has not came back on for over 1000 miles. I was getting a lean code and p0430, p0420. Thanks.

[arbuckle]

Stuck,

Thank you for your post below. I have been trying to make sense of a P0430 (Catalyst System Efficiency Below Threshold (Bank 2)) error and your post may be pointing me in the right direction as to what the root cause of the problem is. Can you explain why a vacuum leak caused by part #17 would affect only bank 2 and not bank 1? Thanks.

Dan

Cats are on the way out.

Do this:

http://www.energeticforum.com/renewa...n-foulers.html

A single non fouler is sufficient to make the cats very efficient. Two of them will make the DME happy with no cats at all.

Bank 2 lean is most likely part #17 here:
http://www.realoem.com/bmw/showparts...79&hg=11&fg=40

The vacuum cap dryrots, splits, and then causes bank 2 to go lean. Order and replace.

[ScottM59]

So long as the cat isn't clogged it isn't BAD IMO.

Over time the precious metals in the cat wear out and cause its efficiency to drop. You aren't being as kind as you possibly could to the environment, but by no means are you pumping out raw gas either...

This should work for a year or two, at which point you might not even have the car anymore.

Used manifolds are certainly a more cost effective option but you have no real way to know how many miles are on them, or if they are any good. It is a MAJOR job to R&R these suckers and how much would it suck to install a used set and have the same problem...

I just received the P0420 code on my 530i, 182k on the odo. not sure if O2 has ever been replaced, i have owned about 8 months. Tried accessing the link to your non fouler mod but link will not open. Can you repost or attach that write up here?

[JimLev]

Stück hasn't been around these parts in a while.
You want to look up spark plug anti-foulers or O2 extenders (eBay) that will move the tips of the O2's out of the main exhaust flow. These aren't to be used on the O2's closest to the engine.
I bought some (straight and 90° ones) before I removed the pre-CAT's to install headers just to have them on hand in case I needed them.

[jicaino]

So you know a thing and two about BMW software and you think you're a hot shot! Listen son, at then end of the day you're what you are still have to wake up and go to work, listen to the wife and her to do list, and if you have children about to go college you will be worry how the heck you're gonna pay for that.

Be humble!

He's not cocky and for the knowledge he has dispensed over here in the past, I can say he's humble, as to it was presented in a way that wasn't flashy or arrogant or anything but laying facts and always "I did this" not "I'm a genius that came up with..."

You may be stinged by his precise use of the word "ignorant", but that's no insult. As to the point of the thread in question, you're showing lack of proper knowledge and still chiming in with advice, incorrect advice, to be more accurate, which is a perfect qualification for falling under the label of "ignorant". For a guy that has devoted many many hours reading, experimenting and getting greasy fingers and busted knuckles gathering hands on experience, that is somewhat irritating. He still called you by a precise, non offensive term.

Then, ontop of the incorrect advice, you lay a condescendent "listen, son"... which is the guy-getting-older-patronizing-way-of-saying "I'm wrong, and I'm ignorant, but I can't SFU and will still keep on chiming in, this time with life advice"

One thing's being wise, other thing's knowing, other thing's first hand experience, and other thing's aging up. They're all not necessarily compatible or mutually inlcusive/exclusive.

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And just to prove my pint, I replied to an almost 10 years old thread that I don't know how it ended up so far in the "new content". Who's the dumber-as-gets-older now?