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What Is The A.I.R. System



Wondering what this is in the electrical center under the hood.

Just Curious .

Need more info. Were under the hood did you find this? Only thing I could find in the book is Axel Identification Rear. Don't think you would find this in the electrical center under the hood
It is on the cover to the underhood electrical fuse/relay/ load center as AIR... in the row with the large fuses closest to the engine. I believe it is the 4th slot from the left & 30 or 50 amp . I looked up in the the owners manual on page # 6-69 but all it says is "A.I.R. system" ......... Curious as to what this stands for.
A.I.R. refers to factory installed air pump emissions systems - this is a California thing - affects headers, multiple cats, and a whole bunch of things that make my head hurt. ;D
The acronym stands for Air Injection Reactor.

You mean that non-Cali Av's don't have this feature? I'll have to go look under my hood! Is this one of the differences between the 'dirty' Av's and 'clean' Av's discussed in a thread some months ago?
I actually purchased my Av in California, even though I live in AZ and this was one reason I almost didn't.... but it had everything else I wanted (and didn't have what I didn't want!) so I did it, but yes, I think they have some equipment on them you won't find on other Avs... such as the A.I.R. pump probably.

I think they've generally got them running clean without too much loss now, but back in the 70's and 80's the "california edition" of any car would be rated at 10-15 less horsepower than the "federal" (everywhere else) version.
Thanks All answering my question....... Just one of those things I discovered while exploring my new Av...... The best part is when I was searching for an answer on the web ...I stumbled accross this site ...... My new favorite place. :)

Thanks for the info....

Crexis said:
I think they've generally got them running clean without too much loss now, but back in the 70's and 80's the "california edition" of any car would be rated at 10-15 less horsepower than the "federal" (everywhere else) version.

Not all California cars were cursed with less HP. The 1980 Triumph TR-8 was an exception. This car was similar to the TR-7, but had an "extra" bulge in the hood. And an extra tailpipe. Oh ya, and four more cylinders! British Leyland slipped in the GM Rocket Fire V8 , to which they acquired the rights. The 49 state version had carbs. The CA. version had to go to fuel injection to meet emission standards and because of this, it had 10-15 more horsepower. I, unfortunately, had the 49 state version. In 1981, all 50 states got fuel injection. These were the only two years the cars were made. Triumph went the way of the Edsel shortly thereafter. Pity.
Remembered this antique thread when looking at the fuse panel the other day. FWIW, there's no fuse in the AIR slot on my CA emission Av.
My 03 AV does not have an air pump. I haven't seen any difference in federal (49 state) and california vehicles in quite a few years now.
According to 4X4review.com, because the catalytic converter is moved closer to the engine via 2 small volume pipe converters, the operating temp is reached more quickly leading to better emission performance.

The cat con system is so efficient that the AIR (Air Injection Reaction) system is no longer needed, thereby reducing vehicle weight and complexity.

As such, the 5.3 L Vortec meets ULEV (Ultra Low Emission Vehicle) requirements in CA and northeastern states.


I have seen a lot of Honda cars with the "ULEV" stickers in the lower right hand corner of the driver side window.

In my opinion, the AV should get the same sticker--this should shut all the tree huggers up. :p

Arizona used to have a program offering consumers a grant of up to 50% the purchase price of a SUPER ULEV (SULEV). The program went bankrupt I think because there were so many Arizonans who bought these state subsidized ricers that the fund went dry.

Oh I can only dream up this headline:

Arizonans Buying AVs at 50% Off! :eek:
There is no visable difference between the ca and fed models. Actually for quite some time from about 92 or 93 on up.