avenger09123

I got the manuals for the car for christmas, and I will be implementing this setup for my car when I get my headers in 2 weeks, I have SAI which sucks, but I think I found a way around it. If anyone sees any holes in this theory I would like them to point it out.

These are the CEL codes you get for a failure on the SAI system itself:

P0411--An air system insufficient airflow
Means air pump isn't putting out as much as it should be for some reason

P0412--an air valve relay coil circuit fault
the switch that opens the air valve is faulted

P0418--an air pump relay coil circuit fault
the switch that operates the air pump has been faulted

P2430--an air pressure sensor stuck in range
air pressure sensor doesn't show increase or decrease (like a stuck guage)

P2431--an air pressure sensor range performance
air pressure sensor out of range either too high or too low

P2432--an air pressure sensor signal voltage below the minimum range of the sensor
Duh

P2433--an air pressure sensor signal voltage is above the maximum range of the sensor
duh again

P2440--an air system airflow leak fault condition has been detected
there is a pressure loss somewhere in the system, or the pump isn't working right

P2444-- an air pump stuck on fault has been detected
duh again again

Now the air pressure sensor is on the valve, right as the air enters the valve....not on the exit. So, in theory, you could run this system without having it connected to your headers, now the amount of air the pump through that tiny opening is small compared to the 62.1 Cubic Feet of air your car pumps through those headers in 1 min at 800rpm idle. that being said, GM also writes this - You will get a code for these things: "partially blocked or leaking system, malfunctioning pump, malfunctioning valve/pressure sensor, restricted exhaust between the cat and your headers, malfunctioning pump/valve relay"
READY FOR THE GENIUS OF MY IDEA muwahahahaha????

None of these faults address no connection to your exhaust or low pressure after the valve. The only sensor that would read this air is the one in the catalytic. and when your pushing 62.1 CFM of exhaust through your headers, trust me when I say the o2 sensor in the CAT will not notice the lack of fresh air from the SAI. So this leaves a couple things up to question.

What happens if I just disconnect the SAI air going to the exhaust manifold -
Answer: there really shouldn't be anything that happens no cel and nothing on your IDD

The pressure sensor on the valve, wouldn't that detect the air pressure of the system overall?
Answer: Yes it might, which is why I'll be disconnecting the SAI from my headers in my car this weekend to give it a test run. If it does make a CEL, all you have to do is get a smaller diameter rubber hose on it and maybe even plug the end of it a little with an air fitting or something to increase the back pressure just like it was plugged into the headers. But the GM manual says its specificially on the way from the pump to the valve, not the valve to the headers, and all the error codes are not what would occur after the valve, only between the valve and the pump. (if you ran your car at 6500rpm right as SAI kicked on, I can guarantee no air would get into the headers because of so much pressurized exhaust, so it is clearly on the pump to the valve)

What happens I just want my SAI to work right with my performance headers?
You can drill a hole in the downpipe and tie in the rubber hose there, as long as it is before the cat, it shouldn't be an issue if my way doesn't work either.

I am going to be trying this on friday, I'll post my results probably friday evening, if it works out right. I hope it does, my ceramic headers are calling my name.........

BigTizzle903

you could also find a dealer that has a Tech II and also is willing to flash out SAI and then u dont have to worry about it at all, it will be like u bought a brand new car and it never had SAI

avenger09123

yeah tried, that, no chevy dealership will will flash them out and the shops around won't touch them either because of the federal laws from emission standards....as in years of prison time for them. Only the poeple up in maine got the good gig.....bastards

BigTizzle903

oh. the dealership down the road said they wood flash mine out for me. just havent had the time or the energy to actually go and do it

tonio5555

Theory is plausible, but probably just easier to find a Tech II and flash it out?

BigTizzle903

yea theres a thread somewhere on here about what dealerships have a tech II and which ones are willing to flash out what.

tonio5555

Only places I know of are Crate Engine Depot in Illinois and some guy in Maine. Either there or you have to have a god friend at a dealer that will do it on the side.

BigTizzle903

idk. my friends dad owns a body shop thats connected to the chevy dealer down the road from me. i had my friend ask them if they had a tech II and if they did would they be willing to flash out my SAI and they told him they wood.

avenger09123

you guys are lucky, people over here are so scared shitless of anything bad happening they don't want to touch it, we have like 7 chevy dealers here and none of them said ok......I might do some calling around and find if any dealership outside of town will do it.....hrm a hunt for this afternoon would be the tech II out at the custom shops I haven't tried yet.

avenger09123

ahhhhh the sweet smell of success.....the man won't keep me from my performance headers!!!!!

Well ya'll I unplugged my SAI tube at the header, and viola, no check engine light and a meaner sound

Heres a pic of what I unscrewed from the header - the end of the metal tube on the header itself



and here's what it sounds like: a short clip-

http://www.youtube.com/watch?v=EMUZa4IMbwo

This is my modification, if you try this, you try it at your own risk.

BigTizzle903

it sounds a little weird. if it aint bad it sounds pretty good

HunterKiller89

iTrader: (1)

umm...yea. I actually did this already, and posted about it in the SAI sticky....and guess what...i got a code.
P0411--Secondary air system insufficient airflow.

thats the only code, as the pump is still connected and still flows, but is not connected into the header. I didn't have a code for a couple days, but it will come.

avenger09123

That sucks....but that code, P0411, thats a code related to an SAI system failure only(saying that its not pumping enough air to keep the pressure sensor at a normal voltage). The way around that is to stick a valve at the end of that hose so the system is still putting air out but keeping a lot of backpressure like it would in the headers....or your pump is clogged or broken. I'd think your o2 sensor in the exhaust would give you a code if anything....hrm weird....maybe I'll dive into that one this weekend......

HunterKiller89

iTrader: (1)

ill give that a try. codeless SAI removal would always be nice

avenger09123

Yep I'm going to plug the hole in the headers on friday while my friends redoing his rotors and see if I can run in the entire weekend without SAI plugged in, nice rubber plug should do the trick. which means races friday night(unless its raining) and then illegals on saturday night.

HunterKiller, if you get a CEL, gimme the code.....