Rear cats??

[SGTFRY]

If you remove the rear cats will it pull a code???? thanks,,,,Sgt Fry

 

[TheMoparConnection]

FOR CAT EFFICIENCY YES

 

[Annu Kumar]

Hey Bucke I would think if you have the other 2 Cats Ot should be fine than.
No codes if you still have 2 Cats left?

 

[TheMoparConnection]

Hey Bucke I would think if you have the other 2 Cats Ot should be fine than.
No codes if you still have 2 Cats left?

IT'LL THROW THE CODE

 

[moparracing]

IT'LL THROUGH THE CODE

are you sure if you remove the back two cats that it will throw a code ??
i've had mine off for a year without any codes ..........

 

[FlyingLow]

Rear cats will not throw a code. The fronts will unless you put in sims.

 

[TheMoparConnection]

THAT SURPRISES ME, BUT I HAVE SEEN IT THROW A CODE FOR REMOVING REAR CATS ONLY. HAD AN 04 IN THE SHOP WITH JUST REAR MISSING THAT THREW THE CODE

 

[JR_PRO]

If you left the stock OEM cats in place but they were gutted, does that void your warranty?

Thanks!

 

[Annu Kumar]

How about high flows in the front Bucke!

 

[moparracing]

If you left the stock OEM cats in place but they were gutted, does that void your warranty?

Thanks!

warranty is such an iffy thing....... what it will do is require you to put on sims or have your pcm flashed to eliminate the cel.......

 

[ViperTruck2933]

Just replace your midpipes with new mids and high flow cats. Mine does not throw codes, performs just about as well as no cats and will pass inspection. :rock:

 

[SGTFRY]

Well I'm welding a custom exhuast so I'm tryin to cut the back ones but if it sets codes i won't.

 

[FlyingLow]

Rear cats should not throw a code. There is nothing there for the computer to read from. The front cats have sensors on them so they will throw a code. If you remove all your cats you only put sims in where the fronts cats where. You don't add sims to where the rear cats were as there isn't any thing there to connect it too.

 

[SGTFRY]

See thats what I was thinkin!

 

[mauiSRT/10]

Dump em all and put in Boomers inexpensive sims and enjoy the cheap power!!!!

patrick

 

[Muzzy]

There are four O2 sensors on our trucks. Two are upstream and two are downstream from the cats. The upstream (two closest to the engine) O2 sensors are what the PCM uses to check air/fuel ratio. They are necessary for the engine to run correctly. The downstream sensors are used to check catalyst efficiency for emissions. MOST cars will throw a code if you remove your cats because the downstream O2 sensors will detect too low O2 (meaning cat is not completing the burn of excess hydrocarbons from combustion). It puzzles me why some of our rigs do not throw codes when removing the cats. I theorize it has to do with oxygenates blended in reformulated gas of certain regions. If you remove your cats and get a code, just purchase some simulators to plug in place of the downstream O2 sensors.

-Muzzy

 

[moparracing]

There are four O2 sensors on our trucks. Two are upstream and two are downstream from the cats. The upstream (two closest to the engine) O2 sensors are what the PCM uses to check air/fuel ratio. They are necessary for the engine to run correctly. The downstream sensors are used to check catalyst efficiency for emissions. MOST cars will throw a code if you remove your cats because the downstream O2 sensors will detect too low O2 (meaning cat is not completing the burn of excess hydrocarbons from combustion). It puzzles me why some of our rigs do not throw codes when removing the cats. I theorize it has to do with oxygenates blended in reformulated gas of certain regions. If you remove your cats and get a code, just purchase some simulators to plug in place of the downstream O2 sensors.

-Muzzy

what he said !!!

 

[chase]

Sims

Where can I get the sims and how much? Also, what is hp gain from just magnaflow cat back vs. gutting the cats and the magnaflow cat back. Sound diff...how much louder if you do both vs just the magnaflow?

 

[FlyingLow]

There are four O2 sensors on our trucks. Two are upstream and two are downstream from the cats.

True, but they are on each side of the front cats. The 2 down stream sensors are behind the front cats. There isn't anything in-front of or behind the rear cats.

 

[Muzzy]

True, but they are on each side of the front cats. The 2 down stream sensors are behind the front cats. There isn't anything in-front of or behind the rear cats.

Correct, there is nothing checking the efficiency of the two rear most cats. Personally, I would remove them all. I hate winter and am looking for some mid-west beach front property... Plus it's cheap horsepower.