high flow cats + CELs

to my understanding high flow cats should not throw CELs?

I'm asking cause I was speaking with a fchT member
who claims be getting right bank o2 sensor cel with a set of Nouvalari 200cell hf cats.

this peaks my curiousity as I was looking into getting a set to complement my Nouvalary SS exhaust.

I know some people put spacers even with hf cats to be extra safe.
nonetheless the cats alone should still not be triggering any lights.

please report those who are running hf cats, brand and if spacers or not and if getting any cels.

thanks.

 

I've had great luck on my 355's with the Fabspeed Headers, 200 Cell Cats-with the 02Extenders !!!
No lights and smooth running!!!! Great Set up
Mike )))

 

I'm against O2 extensions. I ran them with high-flow cats but some people in the know set me straight. CELs provide valuable information. If your tricking your car your car you might miss something. Bruce aka bcwright can shed more light on this. I run hyper-flows and never had a problem. These were recommend to by Fchat members that run them with no problems. If your cats are triggering CELs or you need extenders it's time to switch cats. Typing on iPhone please excuse my mistakes

 

I run hyper flows with CEL until the extenders are installed. Everyone I know with hyper flow cats have the same CEL problems. My car and their cars do not pass california smog test. Everyone that i know.

 

Question .... What type extenders ?
Picture ?
Or make ?

 

I have hyper flows with no extenders and no CEL. OBD2.

 

Iam using the Fabspeed 02 Extenders

 

Call Russ at Ferrparts. I just gave him a set of Fabspeed O2 extenders. Hyper-flows OBD2. No cel no issues

 

I am the F chat member mentioned above. PO installed Fabspeed headers with ceramic coat (black) he also installed Nouvalari cats and exhaust. The first 3K miles I drove the car nothing, then got the P0422 and P432 CEL codes, reset it came back. Indy shop recommended spacers/extenders, I bought the $150 Fabspeed spacers, rather large and L shaped, say 2" each way. Took 4 hours to install he had to take the cats off. Now I get these two codes P0139, rear oxy sensor slow response, bank 1 sensor 2. Also get P0133 same issue bank 1 SENSOR 2.
Possibilities just guessing, faulty sensor, wiring frayed/faulty, or exhaust leak.
Odd they both come up on the driver's side under bank 1 ?
I am open to any and all suggestions, I am at a loss here to correct this.
Thinking shorter spacers, straight 2" ones ? Anybody have a fix for this ?

 

I have owned my 97 355 spider for 14 years now, I had 3 different high flow cats installed threout my ownership, 1 set lasted about a year before I got a CEL, the others lasted a couple months, I was glad I didn't sell my OEM CATS as I now have them installed back and I have no CELS pending any more. I do have a couple sets of high flow 200 CEL cats in my parts collection if someone wants to buy shoot me a PM.

 

well it's evident just from the few replied here
that running high flow cats is not consistent.

as just here replies range from no issue to getting cels with and/or without 02 spacers

this is bizzar. high flow cats should not be throwing cels even on the delicate 5.2 cars.
I've run hf flows cats on other cars with no issue at all and many years/miles with them on.

test pipes are another story. would never use them on a 5.2 car.

nouvalaris cats are priced very well $1200 for the set.
I beleive hyper flows are in range of $2500.

this is disturbing me now.
on a 5.2 car high flow cats should be plug and play no issues.

this leads me to beleive those who are getting cels with hf cats on is a sign of other issues not the cats.

 

Eyboro ...
So you have had THEEE sets of after market cats and all of them produce a CEL within a few months ?
Damn I might need those high flow 200 CEL cats you have laying around.
Curious what brands the three mentioned were ?

 

I seriously need to find/discover that "other issue"

 

the Nouvalari cats you have are 200cell?

are you running Nouvalari test pipes or their high flow 200cell cats?

 

p0422= cat effeciency below threshold bank 1
p0432= cat effeciency below threshold bank 2

these occurred before you did anything.

then yu put the spacers. and codes change to
p0133= o2 sensor slow response bank 1 sensor 2
p0139= o2 sensor slow response bank 1 sensor 1

something is happening here.
what looks to me is you must have test pipes not high flow cats.

after installing the spacers it partially corrected the problem with test pipes
but thats the problem with tp on a 5.2 car. it will never work cel free.

odd with the spacers on your are getting a o2 sensor 1 issue
I would think this should not be happening.

 

agreed..its easy to mix up straight pipes with an outside canister that looks like high flow cats... I know because I did it.......like I said earlier O2 extensions can mask problems..it might not be the cats

 

These are the cats and exhaust
Image Unavailable, Please Login

 

Tp on a 5.2 car ? Explanation please, and see the order form for the Nouvalari cats and exhaust.
I do not think they are test pipes ?
Sorry about the blurry pic.

 

I don't have Nouvalari CATS, I have Stebros, Evoflow, and some English brand BM! all are high flow 200 cel CATS

 

When I called the shop they said with the P0133 and P139 they thought the spacers were to long, and mentioned they usually installed the shorter ones.

Your sequence of events above is correct.
Still strange to me everything (CEL) related is all on the driver's side or bank 1 ?

 

Picture of the shorter adapters/spacers I will install if I don't get another option to research.
Image Unavailable, Please Login

 

Shootdighter65
I sent Bruce a PM and told him about this thread, hopefully he will reply or add something.
So you have Hyperflows and have no problems ?
Do you have a link or website where I can price these.
Having already spent $550 on parts and labor To fix this, well you know how this goes lol.

Odd note on the Nouvalari invoice ( above ) it does say "lifetime" guarantee under the cats.

 

Bruce knows more about this than me...I had codes on the left bank only turned out to be a loose O2 sensor. I have had good luck with the hyperflows. They were on the car before my friend bought it and when we went to put test pipes on we discovered one was rattling. After the test pipe looking cats turned out to be $h!t I sent them to hyperflow to be rebuilt they said this was the old style they dont make any more. They sent me a reconditioned set and been fine since...I dont know about playing with different size extensions I believe if the car is running right with the right equipment you shouldnt need them...its like a band aid it doesnt heal the problem

 

If you want the CEL to go out with high flow cats use 90 degree extenders.

 

I have hyperflows, no extenders and no CELs.