I purchased a brand new Airaid CAI thinking I’d give the LS3 a bit more air. I read many discutions dealing with CAI (wow - people are passionate about their CAI!). Anyway I decided to buy the Airaid air filter assembly.

I installed it on my car. Disconnected battery overnight. Then I drove the car for about 300 miles and sure enough, the dreaded CEL came on with the P0171 / P0173 “lean left and right banks” codes.

And NO, I DON’T HAVE A VACUUM LEAK! NOWHERE. No other mods on the car.

Plugged the scanner and my LTFT was at +21% at idle and +18% average on both banks on highway. Intake Pressure and intake temperature match the tables. So MAF good. Also MAF and MAP don’t code. I checked all connection, checked hoses, pipes, and everything on the car. All is good.

I reinstalled the OEM air filter assembly and everything is back to normal. Instantly. LTFT at +-1% at idle and on highway right there after initial start up.

Therefore my conclusion is that the LS3 is not meant for a CAI. If a car has no CEL after installing a CAI it probably means the LTFT are within range to keep the CEL light “off” but still at +10% LTFT. The CEL is caused by a poor design in the Airaid CAI tube at the MAF. Since there is turbulence right there, there’s no chance to get a proper air reading by the MAF. Adding a tune would not solve the intake turbulence issue. It would just add a “patch” on the tables to keep the CEL “off”.

I’d like to hear from owners with a C6 LS3 with the following matching conditions:
-CAI installed
-no other mods
-no tune
-no CEL

What are your LTFT at idle and on highway?

Thanks !

 

Interesting. What scanner are you using to tell you where the fuel trims are at? I've got a custom tune after a 116 cam and ported heads on my LS7 and am now wanting to install an Airaid, but am uncertain if I can install it before driving 10+ miles into my tuner to get a retune. I know stock the motors are set awfully rich so one of the first things they do in a tune is lean out the AFR a little and theoretically, adding an Airaid is going to only add a lot more air (that's the hope, right?) to the MAF and I'm afraid my fuel trims won't be able to handle it. Interesting that it took 300 miles for the CEL to trip.

How are you able to conclude that the Airaid has a poor design in the intake tube? Plenty of other Airaid's and CAI's on LS3's and others in this forum. AHP uses them a lot on LS7's with tunes with great success.

If the Airaid is giving you that much more air, get a tune to take advantage of it.

 

You didn't come to the conclusion that the ls3 is "not meant for a cai," you merely found out that you should get a tune to clear up these issues after install. More air in, more fuel required simple as that.

 

First off, the Airaid is not a CAI.
It still pulling air from the hot engine bay, Not from out side the engine bay area that has cooler air isntead.


Secondly, it can cause problems with the flow through the MAF being less than stellar, so some times tuning is required so the ECM can read what air flow is coming through the air filter system.

To be blunt, if you don't have a mod'd engine that requires more air flow that what the LS3 is already offering, then you gain nothing with the Airaid system; other than just being able to hear the car sucking air louder instead.

 

Thanks everyone.

To answer a few questions above: I’m using a wifi connection to my iPhone for the scanning and data logging. Never had any issue with the accuracy of the data. As for the tuning, I can’t understand what a tune will do to correct air turbulence at the MAF. A tune for a stock LS3 will only change the tables so the CEL doesn’t come. This is not what I want and this is not what an Airaid system should be.

When you analyse the OEM filter you’ll notice that the filter is quite deep and has small “tubes” across the filter. I’m pretty sure that the filter helps in providing a laminar airflow thru the MAF, thus getting a very precise reading in air flow. Check ou this review from an airflow engineering standpoint :

Turbulent vs Laminar Flow

Laminar flow is where the air is flowing through the tube in parallel layers, with no disruption between the layers, and the central layers flowing with greater velocity.

Turbulent flow is when the air is not flowing in parallel layers, but direction, velocity and pressure within the flow of air become chaotic. If airflow becomes turbulent, the pressure difference required to maintain airflow will need to be increased, which in turn would increase turbulence and therefore resistance.

This means that turbulence leads to a need for a much greater difference in pressure to move the air.

I Agree with Dano523 that an Airaid is not a true CAI. A tune would shut the CEL off but it won’t fix the real,issue at hand: how to fix turbulence in an Airaid pipe. The database in LTFT gives hard facts: when there’s turbulence and when there’s not.

Am I getting this wrong?

 

A tune will allow you to do more than just turn off cels, but I won't get into that, and having had an airaid on my ls3 I can tell you that the maf data was always smooth. Enjoy your stock intake!

For the record ltfts are not merely an indicator of turbulence I'm not sure where you got that idea.

 

Thanks for the reply. The way I see this is the turbulence is causing bad MAF readings and the O2 sensor is trying to correct the fuel ratio. It does that with the LTFT.

It’s very clear to see the problem - at least on my car: when you simply switch the 2 intakes and look at the trims Its instant. OEM at 0% LTFT, the Airaid at 15%.

Anyway, I’m still looking to see if someone has an Airaid intake with a LTFT at or near 0% without a tune. Headers or not doesn’t matter.

There are several posts on the forum that talk about this very issue and would like to find out exactly how to solve the turbulence issue.

Thanks!

 

We have sold and installed a bunch of these intakes and haven't had any issues with them causing cels. Seems like your car isn't agreeing with the intake (cars can be temperamental with some mods)

A honeycomb airflow straightener can reduce any turbulence if you can find one that fits before the maf.

 

A honeycomb MAF? Would you have some kind of reference or product to recommend? I believe that would really help. It would mimic the OEM air filter "air tubes"

Regards,

 

I found an image that really show the differences between both filters. The image is an AFE filter - The Airaid filter is identical. You clearly see the OEM air filter "Tubes":

 

Second picture in thos post is an example of a honeycomb that sits in front of the MAF. https://www.corvetteforum.com/forums...post1597323495

Having said that, I'm not sure how you'll fit one in the Airaid intake and have it stay in place.

Maybe just install a "vette air"...that will push cool ambient air right to your OE filter. I have read of MAF turbulence issues with the vette air as well though...

 

It isn't a turbulence, as much as different cross sectional area across the maf area. The maf is calibrated for a certain size opening, the air aid has a much larger free flow opening, therefore the maf curve may need adjusted for that. Some cars have enough adjustment to not set a CEL, others do not.