O2 snesor/exhaust recirculation- 88k5

[bigred88]

So I just put new headers on my 88 k5 (the drive through colorado springs with open headers on the way to the exhaust shop at 9pm was great! with the occasional backfire at idle I scared the crap out of a guy sitting next to me at a red light). My question is- can I just take off all the o2 sensor and exhaust recirculation stuff that was on there? It did just fine on the way to the shop without it (I'm assuming the backfiring I mentioned was because there wasn't enough back pressure, correct me if I'm wrong), but I didn't know if there were any unseen consequences. If I'm right (which is rare, so...) then the o2 sensor is just there to tell the computer how much exhaust to recirculate, then the valves open depending on what was needed for a more complete burn. I'm already taking the cat off, and I don't have to have it emission tested, so I'm not worried about the legal stuff, just wondering about what impact taking all that off might have.

 

[4X4HIGH]

You need the 02 sensor. The ECM will not go closed loop without it. Once the ECM goes closed loop is when all the other sensor inputs are seen and the ECM is then able to make adjustments. Without going to closed loop the engine won't run at it's best and will definately take a big hit in the MPG department.

 

[bigred88]

But I can remove the recirculation crap?

 

[4X4HIGH]

But I can remove the recirculation crap?

Are you talking about the EGR system? If so i would leave it there as it helps to cool the combustion temps which helps to reduce detonation.

 

[bigred88]

thats what I'm talking about. How does it help cool combustion temps? Seems to me like it would raise them, taking hot exhaust gas and dumping it back into the engine. Not too much I can do to put it back on though, there's no port on the headers for it.

 

[bradshawtech]

Two different systems are being talked about here I believe. The egr is as 4X4 High mentioned. You are speaking about the air injection system with the air pump and tubes into the exhaust manifolds. I removed them from mine and no problems from the ecm system. you will need to plug a vacuum line that went to the air diverter valve as well.
How can you get away with no emission stuff in C.S.? I thought that you had emission inspection requirements over there, or is it only Denver now?
You can get a bung and a three wire O2 sensor to weld into your headers just be cautious as to where as it needs to clear shifter linkages and driveshafts depending on where you can put it now that the hedders are on the rig.

 

[bigred88]

el paso county (where c.s. is) did away with emissions test a few years back. plus I'm military with residence in Florida, so I can just switch the registration back to FL if I ever do have to do any emissions stuff (no testing there, either).
I just talked to the exhaust shop (they're doing the work today), and they're going to put an o2 sensor port in the reducer. I've seen that done before, and it shouldn't cause a problem there. I can always route the wiring around anything that would be a problem, anyways.
Fill me in on what the EGR is then (and where)- my other car is a lot older, and doesn't have any emissions control stuff, so I'm still learning all of this stuff. Sounds like you got it right though- a tube going into the exhaust manifolds at the front on both sides. What exactly do they do?
Now that I've finished showing off my stupidity...

 

[dyeager535]

Easy answer:

Did you like the way the truck ran before? Yes? Leave it all there.

AIR on trucks can be removed without consequence as mentioned, except legality and probably slightly increased emissions.

 

[sweetk30]

you will need chip burn to turn off air stuff. and for faster and better performance switch to 3 wire o2 . easy to do and seems to work faster and better as to brian at www.tbichips.com tons of good info there and chips.

 

[dyeager535]

Are you thinking of EGR? There is no "trouble code" for AIR, and AIR in trucks is only used to heat the cat converter up to temp quicker, while the engine is still cold.

This is unlike the car AIR systems, which utilize an O2 sensor "offset" in the ECM to compensate for the additional AIR that is pumped into the exhaust under other than cold engine operation.