Page 1 of 1
Air pump removal
Posted: Wed Jan 30, 2008 11:00 am
by Stiletto
So, after looking on nastysock and digging around other places, I've come to the conclusion that I'll remove my OEM air pump. I was gonna install a new up-pipe anyhow, so while I'm back on the "hard side", I might as well yank that puppy off.
Anyone else done this yet? My only concern is getting the CEL removed via my Cobb AP. I'm not sure if TXS, Mach V or anyone else has adjusted maps for this sort of mod.
Posted: Wed Jan 30, 2008 1:19 pm
by Sabre
ok, I'm at a loss... What does your air pump look like? The only air pump I know of on our cars is the turbo

Posted: Wed Jan 30, 2008 1:27 pm
by complacent
Sabre wrote:ok, I'm at a loss... What does your air pump look like? The only air pump I know of on our cars is the turbo

The 06+ turbo 2.5's have an air pump for emissions purposes.
Sorry, I'm not sure what it would take to remove it and squash the related CEL.
Posted: Wed Jan 30, 2008 3:45 pm
by Sabre
Ah, so they pump air into exhaust to help burn more of the bad emissions? Interesting...
Posted: Wed Jan 30, 2008 4:26 pm
by Stiletto
Yeah, it's supposed to solve the issue of not having a pre-cat. It only runs until the EGTs reach a certain point, then becomes useless. There aren't any real benefits of removing the pump and associated junk, just ~10 lbs. of weight savings. That, and a cleaner looking engine bay.
Posted: Wed Jan 30, 2008 4:27 pm
by avriette
complacent wrote:Sabre wrote:ok, I'm at a loss... What does your air pump look like? The only air pump I know of on our cars is the turbo

The 06+ turbo 2.5's have an air pump for emissions purposes.
Sorry, I'm not sure what it would take to remove it and squash the related CEL.
the same kind of air pump that was called a "smog pump" in the 1970's?
Posted: Wed Jan 30, 2008 4:36 pm
by complacent
avriette wrote:complacent wrote:Sabre wrote:ok, I'm at a loss... What does your air pump look like? The only air pump I know of on our cars is the turbo

The 06+ turbo 2.5's have an air pump for emissions purposes.
Sorry, I'm not sure what it would take to remove it and squash the related CEL.
the same kind of air pump that was called a "smog pump" in the 1970's?
One and the same!
I stand corrected. They added them in 07. For the STi. 06 for the WRX.
Wikipedia wrote:The ECU was completely re-engineered in order to meet US LEV2 emissions requirements, which has caused throttle and timing issues. A secondary air pump was also added to help meet LEV2. Top Feed injectors replaced the Side Feed from the previous models.
Full Wiki page
Posted: Wed Jan 30, 2008 4:41 pm
by Sabre
Hmm, just makes me wish they had added it to be plumed back into the UP... Antilag anyone?!?!?!

Posted: Wed Jan 30, 2008 5:26 pm
by sirwilliam
I have one of those bastages in my '08 FSXT. From what I heard you can just get a blocking plate a resistor(s) to defeat the CEL for it.
Posted: Wed Jan 30, 2008 5:27 pm
by complacent
sirwilliam wrote:I have one of those bastages in my '08 FSXT. From what I heard you can just get a blocking plate a resistor(s) to defeat the CEL for it.
I saw that Bushur Racing makes some plates, didn't really look into the resistor fix though...
Posted: Wed Jan 30, 2008 5:45 pm
by avriette
Sabre wrote:Ah, so they pump air into exhaust to help burn more of the bad emissions? Interesting...
At least with the 70's air pumps (if this is the same device), the notion is the exhaust is hot enough to burn any excess fuel coming out (with carbs this was an issue... but fuel injectors are so much better at metering gas that running that rich is almost unheard of in a stock car), as long as you're pretty close to the exhaust valve(s).
The problem is the pump is driven by a belt, and the belt runs off the crank, and you lose power this way. Back then the pumps were inefficient, and on engines where you had lots of cylinders (like v8's and v12's (think jaguars)), it could be pretty bad. It did work, however, to reduce hydrocarbon emissions.
GM came up with a pretty neat trick they called "PAIR" – pulsed air injection reaction. It's basically the opposite of a header (well, it's exactly the same as a header, really). They figured that as exhaust pulses left the engine, they could suck air from the atmosphere through a sort of clean-air manifold that attached to the exhaust manifold. It, too, worked, and was really kind of clever. But, people being people, decided that this was a smog item and should be taken off their cars, despite the fact that the only loss in power they would have seen was the drag of the exhaust sucking in fresh air, which would have been so minimal as to not register on anything but an assDyno.
It's the same way withe people removing their EGR.
I had no idea we were still including air injection. Why in the hell don't they just train the engine to be a little smarter with its fuel curves and tricks like direct injection?
Sorry to digress so... I've always thought PAIR was cool stuff, and so few people actually know about it. There are so many ways to reduce emissions without hurting the performance of the engine.
Posted: Sat Feb 23, 2008 9:58 pm
by TAPOUT
When we had my engine apart, you could see where the heads have a hole for the air to come in behind the exhaust valve. I would love to remove the air pump and do a CEL fix. I will look into it.