Removing Secondary Air Injection System

[Shdwdrgn]

Just picked up my blocking plate from the dealer today. The price here was $7.22. Where they really got me was in the gasket... $8.69! Ah well, it's a one-shot deal.

The nice thing about the factory blocking plate is that it appears to be sized to the same thickness as the solenoid, so you can use the same screws for either option. Once I get the air pump and hoses ripped out, it will hopefully look like it simply never came with the option. Not to mention removing the pump will help offset some of the weight I gained from my steel bumper

 

[bobdec]

My question is this. Does the A.I.R. system actually cause the Cat to warm faster for reduced emissions, OR does adding clean air to the exhaust lower the Parts Per Million of hydrocarbons by adding more parts of clean air?

The added air (oxygen) assists the excessively rich (cold engine start) exhaust mix to continue burning in the exhaust manifold. It heats up the cats faster and lowers the HC's. Some say cats may clog faster if you have an excessive amount of cold starts w/o air working. Not sure if that's ever been proven..

 

[tmm217]

Did this block off plate removed hoses and pump now to make complete I'm hoping I can find a intake tube from junk yard that doesn't have hose hole. Other than a ses light on this sytem is completely gone

 

[Shdwdrgn]

Was it much work getting to the pump and hoses? I never got a chance to look into it today. What about using a 1" threaded PVC pipe plug and some silicon to plug the hole in your intake?

I have a DIY intake, so just plan on making a new tube without the hole. I also have HPTuners, removing the P0410 code was the first thing I did with it.

 

[tmm217]

its literaly a 10 min job. Remove plug from valve and hose then nut holding trans dip bracket and the 2 bolts. Clean gasket surface and place cover with gasket in place using original bolts. Dont forget to replace trans dip bracket and nut. That simple! valve is located just under/behind intake tube to resonator. Easy accessability

 

[Shdwdrgn]

its literaly a 10 min job. Remove plug from valve and hose then nut holding trans dip bracket and the 2 bolts. Clean gasket surface and place cover with gasket in place using original bolts. Dont forget to replace trans dip bracket and nut. That simple! valve is located just under/behind intake tube to resonator. Easy accessability

I'm familiar with pulling the solenoid... I was more interested in what it takes to remove the pump itself. So far I haven't even seen the pump (I haven't looked very hard). I'm just wondering if it drops out easy or if there's a lot in the way.

 

[AtlWrk]

It sits on the frame under the driver's door and is secured with 3 bolts accessible from the bottom. Simple. You'll probably spend more time fishing the air tubes out.

 

[MJRBrooks]

It's been a few months since this thread had some feedback. Any updates from those that went the cover route? Which route did you take? 3 fuses and all parts/just popped the block in/didn't bother at all except remove the code via PCM4Less/HPTuner? I was going to replace all the parts until I came across this thread. Have any troubles since the "fix?"

Oh and any chance that instead of swapping out the intake tube, just plugging the extra hole? ?

THANKS!

 

[Shdwdrgn]

I spent last weekend underneath my truck, and got a good look at the pump. It seems that it should be fairly easy to completely pull out the pump and the soft hoses, but it switches to aluminum lines over the top of the engine, and feels like they are bolted to the engine some how. Of course the rubber portions could just be pulled out, and the aluminum lines left in place.

I paid a shop once to 'fix' my pump. This involved simply draining the water out of the hoses, then it worked fine... Or so I thought. That Fall I got a code again on the first morning that the temps went below freezing. We had a drought that year, no rain to speak of, and yet somehow my lines were full of water again. The pump worked on and off during that Winter, but at that point I had decided that it simply wasn't worth the hassle any longer and started disconnecting things.

You can certainly just plug the hose connection on your intake (and on the block), and leave it at that. I ran that way for awhile, until I had a chance to make a new intake pipe. If you have no plans to continue using the pump, then you just have to make sure no air gets sucked into places where it shouldn't.

 

[SBUBandit]

I spent last weekend underneath my truck, and got a good look at the pump. It seems that it should be fairly easy to completely pull out the pump and the soft hoses, but it switches to aluminum lines over the top of the engine, and feels like they are bolted to the engine some how. Of course the rubber portions could just be pulled out, and the aluminum lines left in place.

Guess I've never looked at a different year, but I haven't gotten around to yanking all mine yet (trying to time my PCM tune with switching to 08 thermal fan clutch), but mine appears to be all rubber hose. two hoses basically side by side, one from air box to pump, one from valve to pump

 

[Envoy_04]

My entire system is completely removed, except the portion where the lines turn solid and run behind the head. This section is somehow bolted on I believe, and I just left it and removed all the rubber lines from each side. Pulled the relay and two fuses for the system as well, and removed the pump and all the brackets, plus got the blocking plate and new gasket for it from the local dealership.

I ran it for about two days before I got a CEL, which I assume was from the PCM picking up that after a certain amount of cycles the pump had not been working. I had a tuned PCM ordered anyhow, and I've not had a CEL since. It has run this way since early this summer and never had a problem. Start to finish, with cleanup, give yourself an hour to do the removal if it's your first time. Simple removal that I'd recommend, especially if you're getting a tune or have hptuners to turn off the code.

Here's a pic of everything you'll have to take off if you want to completely remove the system. (removing the solid section behind the head is near impossible, and you can't even see it unless you're looking for it, I deemed it not worth the hassle)

View attachment 31044

My intake hose was modified because of my CAI, a K&N 57 series. I wasn't going to buy another CAI tube, so I patched the one that was there. Took a small piece of sheet metal, aluminum like is used for flashing, and cut it a little over 1X1 inch square. Fit this to the curvature of the tube where the hole was, then put a small bead of silicon around the hole, and used some very short sheet metal screws in each corner of the patch piece to attach it. I had the CAI tube off to do all of this, so then I taped it off and hit it with some flat black to match, and when it dried you had to really look to see there was ever even a hole there.

Here's another pic of what it looks like now. Please ignore the dust, I've cleaned up the mess since then! You can see that the tubing is gone and that the solenoid is gone, really cleaned up the engine bay on mine and made it less cluttered. I've also insulated the heat shield on the K&N since that photo with high temp. adhesive reflective heat shield that is used on race cars to help the CAI actually take in cold air.

View attachment 31045

 

[tbags4ever]

Thanks to everyone for all of the great info on this topic. The SAIS has been a thorn in my side for over 2 years. I passed my state's emissions 2 years ago with the replacement of the air check valve. Well, wouldn't you know, the pump eventually went (for a while, my kids thought we had put a jet engine on the car whenever it started up). This time around, I'm done replacing parts, so I want to give this a go. I just have a couple of questions I'm hoping someone can help answer:

1. See the picture. If I send the PCM in to get the 0410 code removed, how does it report for emissions? Will the Secondary Air report as "unsupported" like the "heated catalyst" report? (I'm told on the state's documentation that only one monitoring system can be reported as "not ready"
- I was a bit uninformed about the monitoring systems, so I tried the whole "reset the codes" thing, and got this report.

2. Is there any downside to leaving the other parts there, or are they just dead weight?

Thanks again to everyone for all of the info.

 

[tbags4ever]

P.S. Does anyone recommend either tuning company over the other? (I see PCMforless is now PCMofNC)

 

[Shdwdrgn]

I can't comment on how it will show up in the report, but I can tell you that pretty much ANY software that allows changes to the code will be able to change the value for the P0410 test (you don't have to go to a specialized tuner to get this done). In HPTuners, you can set this to "MIL on 1st error", "MIL on 2nd error", "No MIL light", or "No error reported". I would think the "No error" option would give the best results all around (its also the default for everything that doesn't exist on this platform). That's what I have mine set to, and didn't see anything show up last time I did an emissions test -- then again I don't think our test actually checks all that stuff.

Personally I've set P0410 to the last option, removed my fuses, removed and blocked off the solenoid, blocked off the air hoses... pretty much everything short of actually pulling the pump out from under the frame. If the equipment wasn't there and the computer doesn't report an error, I don't know how the emissions testing could fail?

 

[catgut]

Newb to the site and fed up with this damn air system. My question is are the PCMforLess and HPTuners like the old superchips style programmers where they are only good for one VIN number or can I slip someone a few bucks with one of these to pull this god forsaken code and be done with it?

Thanks

 

[Envoy_04]

Newb to the site and fed up with this damn air system. My question is are the PCMforLess and HPTuners like the old superchips style programmers where they are only good for one VIN number or can I slip someone a few bucks with one of these to pull this god forsaken code and be done with it?

Thanks

PCMforLess, now PCMofNC, is a tuning company. You can send in your PCM and tell em what you need specifically for your vehicle and they'll send it back. They can remove all kinds of codes and the performance aspects of the tune are really great. For a little extra they can send you a loaner so you won't have downtime, and for a little more you can keep your stock PCM and just have them send you a new PCM tuned for your vehicle.

HPTuners is a program, and yes, if you know someone who has it you can have them to take out the code and rip off the SAIS as you please.

 

[catgut]

Great! Thanks a lot for the info. This is for the wifes car so spending the money for a custom tune will be overkill to say the least. I will have to get my ears to the ground for someone who has an HPTuners. Anybody in the Southeast Massachusetts area want to make a few bucks?

 

[Shdwdrgn]

The problem you'll run into is that HPTuners charges $100 to license each PCM, so if your neighbor happens to have it, you'll still have to pony up the cash just for him to write one simple change. If you can find a dealership or a shop that does a lot of work on these vehicles, you may be able to find someone who has an unlimited license, and they may not charge you as much.

If you end up having to spend the money anyway, you might as well go for a full tune. PCMforLess will make significant changes to the engine and transmission performance, and is well worth the money.

 

[The_Roadie]

This is for the wifes car ...

Rather than live with a wife who doesn't understand, teach her the ways of performance and how to be an enthusiast. Unless of course she always drives around with babies and a goldfish bowl on the front seat and gets scared about cornering G-forces higher than 0.002G.

Performance can sometimes get one OUT of trouble, not always used for evil. Take her out for practice.

 

[catgut]

Ha! Love the way you think Roadie.

Thanks for the info Shdwdrgn. I will give PCMforLess a look then. Just hard to put all this money into a 135000 mile grocery and baby getter. If it gets me past this damn air system though it will be worth it. Hell I probably paid for the tune twice with the 2 pumps, 1 relay and 1 check valve I have already dumped into it.

 

[The_Roadie]

... I probably paid for the tune twice with the 2 pumps, 1 relay and 1 check valve I have already dumped into it.

We weep that you didn't discover the community here before you spent that money. We've heard from folks who wasted $1000 at the dealer fixing the crappy system as well.

 

[catgut]

Yeah that really sucks but what are you gonna do. At least I didnt feed the stinkin dealership my money.

Just a couple of questions if you guys dont mind. How bad is it to pull the PCM and do the relearn procedures needed for the new PCM? Just looking for a rough estimate, I can look up the instructions on this site I am sure. Also, do I need to send in a TCM for a 2005 Trailblazer I6?

One more. How do I word the order sheet properly that I want the air system set to Pass?

Thanks again

 

[Shdwdrgn]

Ha! Love the way you think Roadie.

Thanks for the info Shdwdrgn. I will give PCMforLess a look then. Just hard to put all this money into a 135000 mile grocery and baby getter. If it gets me past this damn air system though it will be worth it. Hell I probably paid for the tune twice with the 2 pumps, 1 relay and 1 check valve I have already dumped into it.

If you're going to gut the air pump system, make sure and get the block-off plate to replace the solenoid, and plug the air line going to the pump from the intake side. If you leave the original equipment in place, you will eventually get an air leak that will cause a lot of carbon built-up, and on a grocery-getter that crap will never burn off. Best to just plug the holes and not worry about more problems down the road.

 

[catgut]

I will definitely do that. Ripping out that air system will the best repair I have done to it.

 

[HARDTRAILZ]

I guess I need to remove mine. I deleted the code a year or so ago, but left everything in place

 

[willbill92]

So my SAIS system crapped out a couple days ago. Is it worth it to just delete it? FYI I am in a state that doesnt do emissions tests.

 

[The_Roadie]

The SAIS is only there to hasten the computer's entry into closed loop mode on a cold start. Reduces emissions. If you remove the system, you'll need to pay for a PCM tune to make sure your CEL isn't glaring you in the face all the time. Because then if you offer Sheldon Cooper a ride he'll be constantly pointing out that you should be....like....checking your engine.

The real problem with a permanent CEL status is that you can know why it is lit up at first, but then get complacent, and neglect to constantly check with a code reader if ANOTHER code has popped up that also lights up the lamp.

 

[HARDTRAILZ]

Was definitely worth it to me. I got the tune to remove light and have no issues for past year or two. The tune is money well spent overall, so I would recommend the delete and tune if emissions are no issue.

 

[willbill92]

The SAIS is only there to hasten the computer's entry into closed loop mode on a cold start. Reduces emissions. If you remove the system, you'll need to pay for a PCM tune to make sure your CEL isn't glaring you in the face all the time. Because then if you offer Sheldon Cooper a ride he'll be constantly pointing out that you should be....like....checking your engine.

The real problem with a permanent CEL status is that you can know why it is lit up at first, but then get complacent, and neglect to constantly check with a code reader if ANOTHER code has popped up that also lights up the lamp.

Well my voy always has the check engine light on for some reason. So I always keep an eye on it and in the next couple days I intend of getting a Bluetooth scan tool so I do not go to autozone as often. As far as I know if I get one of these scanners I can check to code to see what is wrong and then clear it correct?

Also how much is a tune normally, being a college student money is always tight. That is why I am leaning toward the deletion of the system. (Cheaper than fixing it)

 

[TB2004]

Had mine done a couple weeks ago and what a difference in performance! Had code removed and all is well. I think the cost is 159.00.

 

[The_Roadie]

Well my voy always has the check engine light on for some reason.

You MUST find out the reason! You can think you're saving money by putting it off until it drives funny, but there are some codes that mean rather urgent things. And other codes that can cost you 2-5 MPG in fuel economy and putting off those repairs is draining your pocket slowly. False frugality.

So I always keep an eye on it and in the next couple days I intend of getting a Bluetooth scan tool so I do not go to autozone as often.

Harbor Freight code readers are almost as cheap as the Bluetooth units. Nobody in your circle of friends has one? You could make money owning one if you just charged people $3 a pop to use yours.

As far as I know if I get one of these scanners I can check to code to see what is wrong and then clear it correct?

Yes, but the proper order is to read the code, FIX THE PROBLEM, then clear it.

Also how much is a tune normally, being a college student money is always tight. That is why I am leaning toward the deletion of the system. (Cheaper than fixing it)

A tune can run you $150. Unless you troubleshoot the SAIS, you can't make a determination if fixing or deleting is cheaper. It might be a $0.20 fuse, a $10 relay, a free solenoid valve cleaning, a free hose drain-out, a $50 valve, a $150 turbine pump, or a $50 O2 sensor. You can't make good decisions without good data, and you get good data by being a good diagnostician with good tools.

 

[willbill92]

You MUST find out the reason! You can think you're saving money by putting it off until it drives funny, but there are some codes that mean rather urgent things. And other codes that can cost you 2-5 MPG in fuel economy and putting off those repairs is draining your pocket slowly. False frugality.Harbor Freight code readers are almost as cheap as the Bluetooth units. Nobody in your circle of friends has one? You could make money owning one if you just charged people $3 a pop to use yours. Yes, but the proper order is to read the code, FIX THE PROBLEM, then clear it. A tune can run you $150. Unless you troubleshoot the SAIS, you can't make a determination if fixing or deleting is cheaper. It might be a $0.20 fuse, a $10 relay, a free solenoid valve cleaning, a free hose drain-out, a $50 valve, a $150 turbine pump, or a $50 O2 sensor. You can't make good decisions without good data, and you get good data by being a good diagnostician with good tools.

I have done all of the troubleshooting and it is the check valve itself and that runs around $170 at the local autozone. All of the fuses and the relays are all good. The O2 sensor was replaced about a month ago. I checked the hoses and they are all bone dry. It would seem that the check valve is frozen.

Lately the CEL has been on because of all the salt getting onto my O2 sensor. the fix that works for me is some O2 sensor cleaner and that clears the code within 20 to 25 miles of driving after the light comes on that is why I am checking it often to make sure it isnt a major issue. Thankfully it hasnt been.

 

[The_Roadie]

What's the specific code? Salt on the OUTSIDE of your O2 sensor wiring harness? Can't you put on some silicone grease to keep the wiring safe from that? Plenty of available products to keep harnesses clean and dry inside. The sensor readings could be affected by the contamination and costing you fuel economy. Plus I've never heard of this specific issue in nine years on three forums.

ADDED: You're using WHAT sort of cleaner precisely? There are sensor-safe cleaners meant for MAF and IAT sensors in your intake resonator path, but I've never heard of an O2 sensor cleaner unless it's meant to clean the active part of the sensor INSIDE your exhaust manifold where salt could never get to it.

 

[willbill92]

P0410 is the exact code that I am getting

The cleaner that I use is made for the o2 sensors its at AutoZone for around 5 bucks

 

[The_Roadie]

I'm not familiar with any O2 sensor cleaner for $5 except one you have to remove the O2 sensor from the exhaust manifold to get at the inside. Are you doing this?

Can you look at the can and post the exact text on it?

And where are you spraying it that clears up your P0410? On wiring? In the intake? In a vacuum line?

Note: I almost NEVER use three of these in one reply.

 

[willbill92]

I'm not familiar with any O2 sensor cleaner for $5 except one you have to remove the O2 sensor from the exhaust manifold to get at the inside. Are you doing this?

Can you look at the can and post the exact text on it?

And where are you spraying it that clears up your P0410? On wiring? In the intake? In a vacuum line?

Note: I almost NEVER use three of these in one reply.

Correction: the code I am getting at the moment is for the Sais system. Also I used the wrong term for the MAF/IAT sensor Sorry about that.

The cleaner I use is CRC MAF sensor cleaner here is what the can says.

The original MAF Sensor Cleaner. Safely cleans and protects MAF sensors. Dyno proven to increase horsepower and improve air/fuel ratio. Reduces rough idle, hesitation and pinging. Improves fuel mileage. Plastic safe, leaves no residue. Use every time you clean or change the air filter.
Proven to gain 4 to 10 HP at the wheels
Safely cleans and protects mass air flow sensors
Safe on plastics
Improves air/fuel ratio and increases MPG

ADDED: The code I keep getting for the MAF/IAT sensor is P0101

 

[The_Roadie]

Thanks. I was worried there was a new thing about the engines I missed.

And where exactly are you spraying it? Sensors have two parts typically - the active sensor part which is inserted into the fluid (exhaust, intake, coolant) that needs some parameter to be measured, and the wiring harness connector side. Sensor cleaners are meant to be used on the sensor side, which always involves removing the sensor from its mount.

I hope you aren't going to say the MAF sensor because 2004 I6 engines don't have one.

Most of the claims on that can are pure crapola.

 

[willbill92]

Thanks. I was worried there was a new thing about the engines I missed.

And where exactly are you spraying it? Sensors have two parts typically - the active sensor part which is inserted into the fluid (exhaust, intake, coolant) that needs some parameter to be measured, and the wiring harness connector side. Sensor cleaners are meant to be used on the sensor side, which always involves removing the sensor from its mount.

I hope you aren't going to say the MAF sensor because 2004 I6 engines don't have one.

Most of the claims on that can are pure crapola.

I use it on the active part of the sensor in the following image. I know that all of what the can says is crap.
View attachment 33468

 

[Envoy_04]

I use it on the active part of the sensor in the following image. I know that all of what the can says is crap.
View attachment 21013

That's your IAT sensor.

I'm a little biased, but I say since a tune is around the same price or cheaper than your SAIS problem, then go ahead and rip that nasty system out of there. Aside from the tune, all you'll need are the new gasket and block off plate to replace the solenoid, and these can be had pretty cheaply at the local dealership. The plate is listed as "Cover" and is part number 12574378 and the gasket is listed as "Gasket" and is part number 24577193. The tune will not only get rid of the code from the now non-existent SAIS, it'll also really wake up your Envoy, it is definitely one of the most worthwhile mods you can do.

By the way, your engine bay is REALLY clean!! Mine looks like crap after this nasty winter, I gotta get on cleaning the poor thing up sometime.

 

[willbill92]

That's your IAT sensor.

I'm a little biased, but I say since a tune is around the same price or cheaper than your SAIS problem, then go ahead and rip that nasty system out of there. Aside from the tune, all you'll need are the new gasket and block off plate to replace the solenoid, and these can be had pretty cheaply at the local dealership. The plate is listed as "Cover" and is part number 12574378 and the gasket is listed as "Gasket" and is part number 24577193. The tune will not only get rid of the code from the now non-existent SAIS, it'll also really wake up your Envoy, it is definitely one of the most worthwhile mods you can do.

By the way, your engine bay is REALLY clean!! Mine looks like crap after this nasty winter, I gotta get on cleaning the poor thing up sometime.

Well when I was in there inspecting the check valve I decided while I'm here why not clean it. LOL.

As for the tune I am getting it for about 100 bucks from lime-swap.