can someone give me a step by step for removing the air stuff. is there anything that you guys that have removed noticed that i should watch for?

can i remove the tubes and leave the smog pump and air going to the cat?

 

sure can. that's what I'm doing in my car.

 

I removed everything when I installed my headers except that I could not get the air pump off. I left it on there for a few months and it stated to sieze and make horrible grinding noises. Since the torx screws were so stripped I was forced into grinding slots into the head if it and got some vice grips on it. It eventually came out after I removed the AC compresser to gain more access. My buddy did the same thing and his air pump started to sieze as well. We took off the whole accessory bracket that the pump is on and took it off when it was out of the car. Sounds like a lot of work but if i ever had to it again I would do the same thing. It was a lot easier that way. You will swear trying to get it off the first time. Some popel can just unbolt it without the torx heads stripping. Are you removing the AIR lines from the exhaust manifolds as well. Those are impossible to get off and you may be better off with a set of headers.

 

you guys may want to look into getting a smog pump idler pulley.

it makes everything look a lot better, and you dont have to worry about it making noises.

-brian

 

since you have a serp set up, your gunna have to get an idler pully to act like the pump. That, or get a shorter belt? But yeah, you can run with the pump still there. removing the diverter valve and all that is pretty simple. Its just rubber hoses and what not. the AIR lines to the cat and manifolds are different.

 

The TPI ECM's (and prolly TBI too) take into consideration air injected into the exhaust, and recalculate 02 voltage. So when you delete the air, the car runs lean, performs less, and is slower.

Enjoy!

-- Joe

 

are you positive about that?

not that i dont believe you, but in all these years of playing around with these cars, i have never heard that...

-brian

 

Yep. I'm absolutely 100% positive..

https://www.thirdgen.org/techbb2/sho...hreadid=213310

 

.

 

I really wanted to express my 'take' on this subject ... especially since I am the one who seems to have brought this information to the front for everyone to view.

I have run without the AIR system with the stock ECM AIR settings for a long time. It has never been a problem. It won't affect WOT at all so you will NOT see decreased performance at WOT ... if anything you will see an increase in performance from reducing weight and parasitic horsepower loss. What might you see from removing AIR during part throttle is an increase in gas mileage from the car running slightly lean at less than 60mph and less than 60kPa.

Tim

 

Interestingly enough, I had the opposite. The second I added air, all my stupid little part throttle issues went away. Of course, this is back when I was asking everyone if the ECM accounted for the 02 being injected and everyones response was "of course not, why would it do that".. gosh i dunno. maybe because theres more AIR in the exaust than is leaving the cyls.

I bought a carsound cat w/out air, and I'm gonna experiement on that for performance, part thottle, and on the emissions machine.


-- Joe

 

But the air that is injected is after the O2 sensor in the cat so it is not picked up.

 

Only when it diverts to the cat (which is truely a lot of the time)

I used to think after closed loop it always went to the cat, but that was me ignorantly trusing GM documentation. Its been proven otherwise, that it diverts to the manifolds while in closed loop under some conditions.

-- Joe

 

This is all very interesting to me - ever since I got my IROC and started learning about the GM emissions systems I've wondered how the A.I.R. works.

An observation - seems as though Tim and Joe had opposite results, or at least very different results, after removing the AIR stuff. I don't know a lot about each of your rides and perhaps there are other factors that helped create no change for Tim and problems for Joe...... Are the results of removing the AIR stuff typically variable with some people having no problems and others getting trouble? Or, is it more common to not have any problems and no need to re-program the ECM/PROM?

The parasitic losses of having to always turn the pump seem very clear to me and I can logically see why getting rid of the pump could free up some ponies. Just don't want any trouble atfer going to all the work to pull the AIR equipment/system. I'm not yet ready to do re-programming so I just want to be sure this would not be needed - sounds like some of you in the know disagree on this.....

Kev

 

Tims not even close to being the same type of setup as me.

Keep in mind, my WOT wasn't effected. But my car had lots of stupid little part throttle quirks. When I added the air pump (simply for emissions testing) I noticed the drivability increased. So I asked everyone if perhaps it was the ECM.

Now on my new setup, my air pump is deleted, and I replaced the 3-way O2 cat, with a 3-way non o2 Carsound (part #94009) cat.
I'm gonna do some emissions dyno testing and see what the difference is in my levels..

Overall performance I think will be effected. Not your straight like 0-60 performance, but your satisfaction in driving. Tim was nice enough to point out to everyone how to turn it off - which was more than I was willing to do because I asked everyone months ago if thats what the code did and they all said "NO!". I never bothered looking. So if your not running an 02 pump, than it should be turned off..

 

so.... what your saying is that your ecm will pitch a fit if you remove the AIR pump? Ok, I need this explained to me. If the AIR pump takes outside air and injects into the manifold, how would taking that out make you run lean? I would figure that the more air you have injected into the manifolds would hit the 02 sensor and make it run lean, and not the other way? I would think taking the AIR pump off would make it run richer, No?

Only way I can see this, is now that there is less air hitting the 02 sensor, the 02 sensor will think you are running rich, and cut the fuel down, thereby adjusting the fuel?

If what your saying about the AIR pump still pumping into the manifold after close loop, then wouldnt the car run leaner WITH the air pump? Either way, Im still taking mine off.

Also, there is something in the ECM that notices that the air pump is there or not? I have never heard of such code? Im sure you could turn off the part in the ECM that diverts the air from the manifold to the cat, but Ive never heard of a code or anything. I have looked it up many times and never noticed a code for it? Either way, the air stuff is coming off. Im leaving the pump on for the cat, but not for the headers. It frees up tons of space also. Space under the hood is like horsepower, you can never have enuff.

 

Its simple logic. When air is diverted to manifolds, it sets a bit. When it checks the o2 voltage, if that bit is set it adds 100mv to the reading. Then it calculates how much fuel to dump.

When you remove the air pump under these conditions, the ECM doesn't know its gone. SO it assumes part of the air in the manifold is from the air pump, so it doesn't add any fuel. The problem is the air in the manifold is NOT from the pump, its because your running lean.


-- Joe