e30cabrio

iTrader: (30)

No cats and this is the sensor code prior to them which is really odd seeing as I just picked up the car and it's a freaking crack at the J shaped appendage the second sensor is attached to on the ART pipe.

What I really don't understand is I have not bottomed out recently so how did it get damaged.


I'll have it welded and see what happens.

Wu-Watt

iTrader: (24)

Hmm your art's cracked too? Maybe we should complain to Tony... ? They are going to break eventually. There should be a gusset welded on for strength..

e30cabrio

iTrader: (30)

It is cracked at the weld. My experience asking Tony for anything has been disappointing.

I plan to take it to a muffler shop in the morning and get a gusset in both and fix that one.

e30cabrio

iTrader: (30)

Had it welded, at a highly respected custom exhaust shop. He said the ARTs are too long, hanging down over 1/4" too far from the body which is why I am scraping everywhere (both flexible links, all of the flanges the bottoms of the arts & the J shaped deals the 02 sensors attach to).

My car is not super low so it is crazy I am scraping so much.

Code has not come back YET.

Wu-Watt

iTrader: (24)

^^ I totally agree about the fitment. I havent said anything because no one else is complaining yet. They are unnecessarily too low.. I'm going to toss em soon.
E30 you should get SG headers for your ill build man!!!

e30cabrio

iTrader: (30)

I have a set of Crawfords that will go in. He is going to cut the amount out of the ARTS that need to go and replace the flexes in my XYZ.

This is the second set of flexes I have had to put in.

Wu-Watt

iTrader: (24)

I thought of modifying mine but... Not till it's etested again..
Is your CEL off now?

pcressey

iTrader: (3)

I just had my motor rebuilt, and after about 700 miles I got both Bank 1 and Bank 2 codes... just prior to these codes I finally gave the car some throttle (still breaking in the motor), and a plume of black smoke came pouring out the back... running rich. I did another test in 4th at 3.5k with 75% throttle and got more black smoke.

The car is going back to the shop Friday for oil change and inspection that did the motor install (not the rebuild)... it will be interesting to see what they say when I bring up this issue.

The car has Fast Intentions HFC, NISMO Exhaust, Motordyne Plenum & Spacer and running on the stock ECU tune.

djamps

iTrader: (1)

I know this post is old but I have to say that this statement is absolutely incorrect -- and I don't care what Shop or Dealer X said... I know this for fact because I spent over a month battling an over correction (rich) issue last year while tuning my car with Osiris. In otherwords, the top o2's were showing rich, yet the ECU was dumping fuel intermittantly...and I couldn't tune my way around it.

Turns out it was being caused by nonfoulers on my lower O2's. Basically if the ECU doesn't see enough exhaust gasses on the lower o2's over a long enough period of time, it'll start dumping fuel even if the top sensors are showing rich... and if it dumps fuel long enough, it'll start throwing codes for your upper sensors since they stay pegged rich. You'll notice it most often when cruising at steady speeds, basically any time the ECU is operation in closed loop long enough, it'll start switching back and forth between upper and lower sensors for corrections.

I deleted the nonfoulers, then deleted the subsequent catalyst codes in oriris and everything is fine now...feels like a new car, no CEL's or overcorrection since, it's been almost a year now.

So... if you're having upper sensor codes you can't get rid of, first try removing your nonfoulers, steel wool, or whatever else you shoved in the lower sensors (either deal with the CEL or erase the cat codes). Don't mess with simulators, it'll only make matters worse.

If after following the above instructions, you're still having issues with the upper sensor codes, then smoke test for exhaust leaks. If you have cats make sure they aren't fouled up -- there's a good chance that all the fuel dumping could lead to your cats failing.

hope this helps...

pcressey

iTrader: (3)

^---

Thanks for the helpful insight. Prior to my FI motor giving out it was blowing smoke for a while, and I had these codes as well as the MAF sensor code (I think). Judging by your experience I am wondering if my HFC are totally fouled out with the old motor blowing smoke for so long... strange for both the non cat sensors to throw the exact same code at the same time on a brand new motor.

djamps

iTrader: (1)

They are probably clogged. Most bolt-on HFC's are garbage and clog even if you're not running bad. The only HFC's I've had that don't clog or crack are 3" metallic racing cats welded into custom downpipes (which is what I run now).

onagao

I don't think your conclusion is entirely well founded. I'm not saying it's entirely unreasonable, but it does fly against something I specifically tested - at one point in this process, I just disconnected the cat-section sensor plugs. So essentially, the car was getting nothing at all from them. Yet even still, the AFR overcorrection issue that throws this code was still there. If the rear sensors are the source of the problem, which I'm not saying they aren't, then why did the problem continue when they weren't even plugged in?

Also, I can't say I've shared any of the too-low complaints floating around regarding the ART Pipes. They fit just as well as any other product I had in the cat section, so I'm not sure there's much to be made of that. However, I do think there's a chance I might have a crack in one of the welds, though every time I've looked I couldn't see anything, and nothing else visual or auditory has pointed me there. I'm sort of at that thought by logical deduction, given that I've eliminated almost every other potential source of this problem.

Honestly, I'm down to either a crack in the cat section, bad injectors, or a bad ECU. Either one of those or my car just hates me and is screwing around with the air fuel ratio for funsies. Possible, I guess.

But also, at one point, I was running with Stillen Headers, ART Pipes, and the Stillen TD Exhaust... which lacks any sort of flex pipe. The end result was heat expansion throughout the exhaust system that caused so much pressure that it lifted the engine up to the point that it would rattle against the strut bar. That sort of pressure easily could have caused some sort of leak in the system that is allowing air to be sucked in during the low pressure section of the exhaust pulse following WOT... and then that tricks the sensor into thinking Lean just long enough for it to jump into "let's dump all kinds of fuel in there" mode.

So I think it could be a leak but have no good way of actually checking it. Doesn't help that I'm in Afghanistan, but even if I wasn't, I don't know of a good way to check 100% short of swapping them out. And that's not a cheap experiment. It would be awesome to have an extra set of ART Pipes to borrow and see if it's just something to do with mine...

djamps

iTrader: (1)

^^ See my whole post. I didn't say the rear sensors ARE your problem. I said they MAY be. You might very well have another issue:

My guess on your issue is bad cats or exhaust leak. We also don't know how the ECU reacts to no sensors at all, it could very well see it as 0 volts (lean) and dump fuel.

onagao

No, I get what you're saying. I read your post thoroughly, and I don't meant to sound like I'm just blindly disregarding what you've said. However, your initial statement that what I said was absolutely incorrect doesn't make sense to me, given what I brought up. The fact that the removal of the rear sensors from the system (by unplugging them) made no difference in the behavior of the problem strongly suggests that it's not part of the equation.

I'm with you on the best guess, though. It seems, from what I've read, that every single person that's had a problem along these lines has found the problem residing in or around the cat section. I just wish I had a good way of finding out.

Wu-Watt

iTrader: (24)

How many f.ucking times do I gotta tell you to take your cats off and have a good look at em'? I have been and done with this issue last year man. Welded the s.hit and no more prob.
Or get a new engine/ecu. Fix er' up good.
*unsubscribing from this never ending thread of onago's brilliant insights.
Oh, read post 104 also. G'damn man. I bet you love to hear yourself blab on and on too, one of those guys.

djamps

iTrader: (1)

^^ +1 anyone having these issues should get a set of good test pipes. most HFC is a joke and cause more issues than they are worth. And when they melt you're SOL.

onagao

Wow. Thanks, bro. I'm in Afghanistan right now, and have been for some time. Perhaps the fact that I've only spent three weeks at home this entire year is why I haven't been able to follow this wonderful advice to your satisfaction?

And despite that I have still looked at the ART Pipes myself, had them looked at by 3 other specialists, and even had the exhaust smoke tested for a leak.

But no, I must just love to hear myself talk.

djamps

iTrader: (1)

^^ didn't realize you had the art pipes. If I recall, those have long extensions for the o2's which will eventually cause issues with closed loop operation -- whether or not you throw codes is hit or miss, but running rich is a given. Disconnecting the o2's isn't a good test because the ecu will still see a bad signal (0v, or possibly worse if it's floating).

e30cabrio

iTrader: (30)

^except for when the extension was cracked My arts threw no codes. The car does not run rich at all as set by my UPREV tune.

pez1111

iTrader: (2)

I know it's been a while but i had the P2a03 code come up. So had the exhaust system checked as i had scraped a speed hump. No leaks, so i was fearing a prolonged fix. So i took the car to my tuner and long story short the number 1 sensor was cooked. At one stage the ecu was dumping 35% more fuel. So i had both replaced . Purring.

My Car '06 track, HKS S/C , tomei headers, Berk HFC's, CBE. Cosworth Plenum, DW 600's, Walbro upgrade. 92XXXkm's (57XXXmiles)