Recent Topics
1991 Toyota Previa New JDM engine Redline
by Kurtatron
06/21/18 06:26 PM
8 yr old channeling John Bonham
by Toy4x4
06/21/18 06:02 PM
Traveller nlgi 2
by Spitter
06/21/18 05:33 PM
Upgrading the Kohler 7000 series air cleaner
by Patrick0525
06/21/18 05:08 PM
Any nano reefers here?
by RichardS
06/21/18 05:04 PM
ARC remanufactured Power Steering Pump
by Pajero
06/21/18 04:58 PM
John Deere "Easy Change" System gimmick
by SnowmanCO
06/21/18 04:55 PM
Oz Planstic Bag Bans - not so green.
by Shannow
06/21/18 04:31 PM
help me choose...
by chaindrive
06/21/18 04:07 PM
France F1 Grand Prix
by DeepFriar
06/21/18 03:16 PM
Valvoline High Mileage with maxlife tech semi-syn
by bradtech
06/21/18 03:16 PM
Best additive in oil to clean sludge?
by ffgb
06/21/18 02:19 PM
Who is a Dirt Track regular?
by thooks
06/21/18 01:39 PM
eco plug oil plug video is restricted
by edwardh1
06/21/18 01:27 PM
Political comments
by ridgerunner
06/21/18 01:23 PM
My Ford orange turned pink
by BeerCan
06/21/18 12:45 PM
Any plants/garden experts?
by maverickfhs
06/21/18 12:43 PM
Internet Sales Tax O.K.ed by Supreme Court
by doitmyself
06/21/18 12:23 PM
Brake fluid for a '03 Volvo S60
by earthworm
06/21/18 11:22 AM
Oil Weight Change - Mid Production Cycle
by PolarisX
06/21/18 11:20 AM
Newest Members
wil892, Spddm0n, ronw1309, Suth31, yamahaboy125
65286 Registered Users
Who's Online
121 registered (aquariuscsm, 97prizm, alphadog, ArrestMeRedZ, 93cruiser, 12 invisible), 1511 Guests and 37 Spiders online.
Key: Admin, Global Mod, Mod
Forum Stats
65286 Members
67 Forums
285727 Topics
4768578 Posts

Max Online: 3590 @ 01/24/17 08:07 PM
Donate to BITOG
Topic Options
#4603059 - 12/13/17 11:38 PM Downstream O2 eliminators
Alex_V Offline


Registered: 04/10/16
Posts: 1155
Loc: Campbellsville, KY
Aside from the emissions/legality concern, will a "dummy" device designed to do away with downstream oxygen sensors (used in a compatible application) affect performance or engine longevity any calculable amount?
_________________________
I like Chevy and Valvoline.

'13 Cruze, 1.4T, 112K
'85 GMC C3500, 454, 130K
'82 Mercedes 300CD, OM617 turbo, 167K
'67 Suburban, 350, 331K

Top
#4603062 - 12/13/17 11:45 PM Re: Downstream O2 eliminators [Re: Alex_V]
bdcardinal Online   content


Registered: 06/03/05
Posts: 10992
Loc: Santa Barbara, CA
Nope. Their only purpose is to monitor catalyst efficiency. You can stack spark plug non foulers and get the same result for less.
_________________________
2014 Ford Mustang GT Track Pack
1995 Ford Mustang GT

Ford/Mazda Parts Counter
NRA Benefactor Member
Opinions expressed are my own.

Top
#4603070 - 12/14/17 12:02 AM Re: Downstream O2 eliminators [Re: Alex_V]
Alex_V Offline


Registered: 04/10/16
Posts: 1155
Loc: Campbellsville, KY
I'm aware of the non-fouler trick. In this case, the moron that replaced the engine in a new customer's '02 F150 (4.2L V6) a few months ago cut out the cats and the downstream O2's, replacing them with several feet of flex pipe clamped at each end. (Yee haw, welcome to Kentucky.) The expense of new cats is out of the question for him (he could barely scrape together the money for me to do intake gaskets) and with the downstream sensors completely gone, a set of eliminators is half the cost of two new sensors that are just going to get non-foulers put on them to keep the CEL off. However, the local exhaust shop (going to put some proper pipe in place of the flex for a good price) won't do the pipes unless they put sensors in them, claiming it'll ruin the engine shortly if they aren't there.

I just wanted to know if I was under the wrong impression about the function of the downstream sensors or not. It appears I was correct.
_________________________
I like Chevy and Valvoline.

'13 Cruze, 1.4T, 112K
'85 GMC C3500, 454, 130K
'82 Mercedes 300CD, OM617 turbo, 167K
'67 Suburban, 350, 331K

Top
#4603185 - 12/14/17 07:08 AM Re: Downstream O2 eliminators [Re: Alex_V]
nwjones18 Offline


Registered: 11/30/09
Posts: 1052
Loc: Warner Robins, GA
Yeah there is no danger in running the downstream eliminators, and they work very well IMO. Best prices I've found are on Ebay.
_________________________
1988 F-150. 4.9 I6 247k. 10w-40 Castrol Syn-blend ACDelco UPF2.
2005 Cadillac STS N* 108k. 5w-30 Castrol Magnatec ACDelco Classic PF61

Top
#4603235 - 12/14/17 08:23 AM Re: Downstream O2 eliminators [Re: Alex_V]
michaelluscher Offline


Registered: 10/07/12
Posts: 2420
Loc: Staten Island, NY
I believe there's a small set of cars (mid 90s Chrysler's) that actually use the downstream oxygen sensor to work in tandem with the upstream

Otherwise, eliminate/space away
_________________________
'06 Toyota Camry SE V6 3MZ-FE 100k
'01 Mercury Villager Estate VG33E 52k
'06 Ford Taurus SE Vulcan 60k
'13 Chrysler 300 3.6 Pentastar 230k

Top
#4603294 - 12/14/17 09:19 AM Re: Downstream O2 eliminators [Re: Alex_V]
MCompact Offline


Registered: 07/21/02
Posts: 4113
Loc: KY
In my experience, the only people that say that 02 eliminators are bad are the ones who want to sell you a new cat...
_________________________
Mine:
2014 M235i
1999 Wrangler Sahara
1995 318ti Club Sport

Wife's:
2016 i3 REX
2009 Cooper Clubman

Son's
2009 328i

Buy what makes you smile...

Top
#4603460 - 12/14/17 11:46 AM Re: Downstream O2 eliminators [Re: Alex_V]
i_hate_autofraud Offline


Registered: 05/19/16
Posts: 705
Loc: Canada


Downstream O2 sensors are part of a second closed feedback loop for the engine module,
they monitor if the up stream O2 are OK and if the Cats are functioning correctly.

You can bet OEMs have lots of code running to validate all O2 since they are critical
to smog controls! The O2 signals change as an engine starts cold and runs til hot and
beyond, the system checks they are outputting correctly under all conditions.

So fake O2s won't cut it.

Top
#4603537 - 12/14/17 01:23 PM Re: Downstream O2 eliminators [Re: i_hate_autofraud]
GMBoy Offline


Registered: 11/22/04
Posts: 7702
Loc: Texas
Originally Posted By: i_hate_autofraud


Downstream O2 sensors are part of a second closed feedback loop for the engine module,
they monitor if the up stream O2 are OK and if the Cats are functioning correctly.

You can bet OEMs have lots of code running to validate all O2 since they are critical
to smog controls! The O2 signals change as an engine starts cold and runs til hot and
beyond, the system checks they are outputting correctly under all conditions.

So fake O2s won't cut it.


Fake 02's and Stacked Non-foulers do, in fact work. I've used both probably 100 times with complete success.

The post cat 02's are just an emission monitor for the convertor's performance. Most cars, true not all, but atleast 80% do not use the post 02 data for anything else.

Top
#4603559 - 12/14/17 02:19 PM Re: Downstream O2 eliminators [Re: Alex_V]
bdcardinal Online   content


Registered: 06/03/05
Posts: 10992
Loc: Santa Barbara, CA
If you want to get technical, Ford calls the rear O2s "cat monitors" in a lot of publications.
_________________________
2014 Ford Mustang GT Track Pack
1995 Ford Mustang GT

Ford/Mazda Parts Counter
NRA Benefactor Member
Opinions expressed are my own.

Top
#4603818 - 12/14/17 07:35 PM Re: Downstream O2 eliminators [Re: bdcardinal]
Alex_V Offline


Registered: 04/10/16
Posts: 1155
Loc: Campbellsville, KY
Originally Posted By: bdcardinal
If you want to get technical, Ford calls the rear O2s "cat monitors" in a lot of publications.


Ha, nice. laugh
_________________________
I like Chevy and Valvoline.

'13 Cruze, 1.4T, 112K
'85 GMC C3500, 454, 130K
'82 Mercedes 300CD, OM617 turbo, 167K
'67 Suburban, 350, 331K

Top
#4603864 - 12/14/17 08:16 PM Re: Downstream O2 eliminators [Re: Alex_V]
Colt45ws Offline


Registered: 08/15/06
Posts: 9640
Loc: Central Washington
Yeah, since this is a Ford I actually have the Ford OBD manual for '01 and '04 that goes in depth about how all the various emission systems work. The rear O2 is just for cat monitoring.
_________________________
-Colton
2002 Ford Crown Vic PI 207k, Ex-Kootenai County, ID Unit #42
Down for engine swap
2003 Ford Crown Vic PI 75k
Castrol EDGE HM 5W30, Fram XG2

Top
#4603909 - 12/14/17 08:58 PM Re: Downstream O2 eliminators [Re: Alex_V]
DoubleWasp Offline


Registered: 05/21/12
Posts: 5236
Loc: Fort Lauderdale, FL
I've used plenty of the non-foulers to great success. Some need a bigger stack than others (Chrysler), but they will work.
_________________________
07 Lincoln Navigator M1 0w-40/FU
68 Charger R/T / Supercharged 440 VR1/DBL7349
07 Ram 3500 4x4 / Cummins 6.7 /DBL7349
17 Maserati GranTurismo Cabrio

Top