Exhaust /cat query

[sssammm]

Looking at my exhaust, i have a cat bypass pipe, but... i still have both oxy sensors still plugged in, i have no engine warnings, any ideas why the downside Oxy has not been removed?

sam

[GTSDave]

Probably to stop you getting a warning light...

[ViperDave]

by both do you mean all four? as in both on one exhaust, maybe leaving the sensor in was easier than plugging the resultant hole. do you have sims?

[brianlewis]

check the rear o2 sensors are not in an extension pipe or similar as this is a method used to retain them in the exhaust without getting a reading.

sssammm said:

Looking at my exhaust, i have a cat bypass pipe, but... i still have both oxy sensors still plugged in, i have no engine warnings, any ideas why the downside Oxy has not been removed?

sam

Edited by brianlewis on Wednesday 8th December 11:09

[viper paul]

Would help if we knew what Viper you had, so others can help.

[sssammm]

Sorry, Gen 3 SRT-10 2004,

both sensors are in situ,one at the bottom of the header, and one on the bend,
and wired, both sides.

A pair of sims are in a plastic bag in the boot,

The reason i ask this is i am going to install a set of S/S
American Racing headers and wondered if i should just install
the upside sensor and put sims on the downside, or just plug them both
in as they are now

thanks
sam

Edited by sssammm on Wednesday 8th December 12:05

[ViperDave]

I'm guessing the answer to that will most likely be a depends... if you fit it all up and you get a check engine light then put the sims in, if you need to take extra effort to fit the rear sensors with whatever you put in then put the sims in.

The only thing you need to do is have the front O2s in place as they control the fueling. The rear O2s are just for emission monitoring

I'm guessing the person that put the bypass pipe in thought they would get a light and brought a set of sims, when they did the change no light came on so they left it be. with the further changes you are making there is a chance you may tip the balance to needing the sims in place.

[sssammm]

Thanks dave, with the exhaust manifolds im getting, it comes with high flow cats, maybe ill try first without them,

or would it be better to put them back in?

[V10 BAT]

Hi matey,i would keep the o2 sensors if you can.
with cats or decat pipes,seems to have no effect on performance
and save`s any probs .and keeps the harness plugs sealed up.
Cats do act like a muffler,so really down to you how loud you want it.
I fitted some roe h/flow cats on my 04 srt,seem to remember the primary o2 was
on the header just before the cat,and the secondary o2 was just after the cat,
like within a few inches either side of the cat.
In pic the new roe pipe has a plug in place of the secondary o2,which i took out a installed the o2 sensor.Maybe have a word with the header guys.
cheers .

[sssammm]

Gonna use these

[V10 BAT]

Hey they look quality,and its not even xmas yet.

[viper paul]

What are the bulges ?? They seem seem to have up stream cats like the originals on the SRT ??

[MADMAX-UK]

sssammm said:

Gonna use these

That's one purty set-a pipes Sam.

[sssammm]

The bulges are high flo cats, but im probably not going to use them