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Cold Air Intake worth the MPG?

drummerdude152002

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drummerdude152002 Enthusiast

drummerdude152002

Posted
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Hey there, new guy here. Don't roast me too hard please!


I'm by no means a mechanic, just a guy who does a LOT of research, and asks questions.

I recently picked up an `03 Yukon SLT 5.3L for the family. Love it, don't love the 13.6 MPG though.

There seems to be an idea all over the internet that a cold air intake kit increases MPG and HP. Some people say "yeah it totally does", some say "it depends on your use case", and others say "it does nothing other than make it sound cool".

So I'm curious...for anybody on the same or similar platform, has anybody had any noticeable gains in MPG switching to a cold air intake setup, and if you did, do you have a recommended kit?

davester Senior Enthusiast

davester

Posted
Posted

Even back in '03 they were spending big bucks on improving mileage.  If a slightly bigger plastic tube could give them even 0.1 mpg more, they would have put that bigger tube on there, as it would be effectively free mpg.

 

And if you want better mpg, get something like an edge cts that displays your current mpg (doesn't really matter if the number is absolutely correct or not), and control how you press on the go pedal to make that number better.

drummerdude152002 Enthusiast

drummerdude152002

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  • Author
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Not that I'm arguing with you, but aren't aftermarket performance products created specifically BECAUSE OEM's don't make things as great as they could?

Just trying to find some truth.

I know there's lots of research that says that the colder the air, the better the performance, and also talk about less resistance on the intake.

Just trying to find out if anybody has done it and have had any calculatable results from it.

davester Senior Enthusiast

davester

Posted
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The stock setup already draws in cold air from the fenderwell (vs some of the CAI's which are literally the opposite, and get air from the engine bay)...

 

Now, if you want more performance, a larger intake and a tune will give you some, but more performance = lower mpg...

Z45 Senior Enthusiast

Z45

Posted
Posted

The aftermarket CAI’s delete the resonator, making the intake louder.  Louder feels faster.  Anything that increases HP decreases fuel economy.

CamGTP Senior Enthusiast

CamGTP

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Consider other factor for your reduced fuel mileage.

 

Like rims and tires. If they are aftermarket or larger than stock, that can lower the fuel mileage.

 

No recent tune up stuff has been done. Like clean the MAF sensor, new spark plugs, make sure you have zero exhaust leaks or intake gasket leaks that would throw off fueling. Intake gaskets and broken exhaust manifold studs are pretty common. Original o2 sensors or just really old o2 sensor could be another cause. Some of this stuff requires a scan tool to watch stuff and make sure it's okay before shot gunning parts.

 

That truck is probably only going to get 18-19 on the freeway, maybe more if you draft and go at or under the speed limit. Combined around 14-15mpg would be normal.

Z45 Senior Enthusiast

Z45

Posted
Posted

Hmm, I wonder why no maker of CAI systems claims they increase mileage.   The computer controls the air/fuel ratio (fixed in the cpu) and when you increase air, it will increase fuel to the prescribed a/f ratio.  How can that improve mileage if you use more fuel?  More air = more fuel = more power =  more speed

 

It defies common sense, which is not all that common.

 

Grumpy Bear Senior Enthusiast

Grumpy Bear

Posted
Posted

Motors are demand devices. They make exactly the power required to overcome the load. No more. No less. Give it that a thought. If they made more than needed they would continue to accelerate and if....you get the idea. 

 

For anything you do to improve mileage it must reduce load. Yes, assuming optimized AFR's. Think GM has that one pretty close these days with closed loop wide band and EPA driven efficiency demands. 

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