Terrible MPG after K&N intake

[AFKNinja]

Hi all,

I installed the K&N 77 Series cold air intake on our 2015 Explorer XLT, 3.5 AWD.

I mainly did this for a nice sounding grumble, but also because someone recommenced this as a fix for the sulfur smell under acceleration. Ironically the installation of this intake actually did fix the smell issue, even under full throttle I don't smell anything (like a normal car)

However I have noticed that my MPG's have taken a big hit. I'm averaging 14.5 MPG in a suburban area, with lots of open roads. Anyone have a similar experience? This is really annoying me as I fix one problem and another arises...

 

[peterk9]

I'm not sure why you experienced a decrease but I know some members after installing a K7N intake went back to stock. I believe the majority though were happy with the mod. Here is a thread that also has the same complaint but also had modified exhaust.
http://www.explorerforum.com/forums...pg-w-k-n-intake-and-magnaflow-exhaust.360473/

Peter

 

[Sgt1411]

Hi all,

I installed the K&N 77 Series cold air intake on our 2015 Explorer XLT, 3.5 AWD.

I mainly did this for a nice sounding grumble, but also because someone recommenced this as a fix for the sulfur smell under acceleration. Ironically the installation of this intake actually did fix the smell issue, even under full throttle I don't smell anything (like a normal car)

However I have noticed that my MPG's have taken a big hit. I'm averaging 14.5 MPG in a suburban area, with lots of open roads. Anyone have a similar experience? This is really annoying me as I fix one problem and another arises...

Did the same on my 2013 Limited, same engine.

My CAI was from INJEN.....total POS, should be renamed HEAI " Hot Engine Air Intake"

I got same results and went back to stock.

Had to eat some humble pie as I was told by some of the Explorer engineers not to waste my time the CAI on a non tuned engine is a complete waste of time and money. But of course I knew better then the engineer that makes his living working on vehicles.

 

[Sgt1411]

Honestly, bang for the buck get a tune, doesn't matter who just get a tune and you will enjoy the improvements and not have to worry about taking anything on or off.

Livernois makes a tune for the natural 3.5L non EcoBoost.

 

[Odrapnew]

What was your mileage before and how long have you had the K&N on?

Not sure why there would be any difference in the sulfur smell with a different intake.
I suppose if it’s running overly rich, it could affect the smell, but then again, I would think the sulfur smell would be worse if it’s running rich.

Also, unless the vehicle was running in open loop all the time, you mileage should not change with the intake change. If it was running open loop all the time, I would think you’d be getting a check engine light.

 

[MikB]

The term 'cold air' is a loose interpretation of this system when it comes to our Ex's. While they are advertised as such, it is more of a legal term to call them 'cold air systems' because they do have a modicum of cold air that blows on the filter because of the reused snorkel from the OEM unit. That is the only distinction, in my view, that they are cold air systems. In reality, again in my view, they air not cold air systems more that they are an aesthetic replacement systems. They do look nice.

That said, it is possible for them to function as a cold air system if you add a cold air box. My Ex is the same model and year as the OP's. I bought the same K&N system as his but, I did it because it would open and clean up the area. Not for any performance claim. For a time I was satisfied just with that. However, I did not care for the noise it made at full or even partial throttle so, I decided to build a cold air system to quiet it down. It is completely insulated made of stainless steel and does the job I intended it to do but, it also has made it a true cold air system with the filter completely isolated from the heat of the engine compartment. In fact, I am using two digital temp gages so I can read temps in the engine compartment and the cold air box. There is an average difference of 25 degrees cooler in the air box with many times up to as much as a 40 degree difference. Whether is gives me any performance at all, I have no idea. The tune I have handles that part. Tunes are a bit expensive but, worth it on the N/A 3.5's.

 

[AFKNinja]

Before I had the intake I could get 20 MPG with highway-ish driving, now I get like 15 max.

 

[AFKNinja]

I wonder if this could be related to something else? My transmission started jerking at low speed starts, maybe something in the powertrain is messed up.

 

[peterk9]

I wonder if this could be related to something else? My transmission started jerking at low speed starts, maybe something in the powertrain is messed up.

Since the transmission issue started prior to installing the intake, did you get a chance to figure out your MPG then?

Peter

 

[Sgt1411]

I wonder if this could be related to something else? My transmission started jerking at low speed starts, maybe something in the powertrain is messed up.

Probably the PTU issue that many were having, get it in to the ASAP to make sure they don't bone you on warranty.

 

[AFKNinja]

Since the transmission issue started prior to installing the intake, did you get a chance to figure out your MPG then?

Peter

The transmission jerk/lurch been going on since before the intake, it's just very subtle so I (wrongly) haven't given it enough attention. This weekend I'll be going back to the factory intake, hopefully I can get a better idea on where my MPG's are

 

[MikB]

I wonder if this could be related to something else? My transmission started jerking at low speed starts, maybe something in the powertrain is messed up.

I wonder if your mass air flow has a good and complete connection.

 

[Turdle]

It could be the pleasing new sound from the open intake causes your foot to create it more frequently.

 

[Magnetic619]

I installed the k&n cai on my 2015 Limited and mpg's went from 18 to 13. The culprit? My foot was on the gas pedal often to hear the intake sound and feel what I believed to be more hp. I kept it on until I traded the ltd for 2017 sport.

 

[AFKNinja]

I installed the k&n cai on my 2015 Limited and mpg's went from 18 to 13. The culprit? My foot was on the gas pedal often to hear the intake sound and feel what I believed to be more hp. I kept it on until I traded the ltd for 2017 sport.

I try to drive conservatively to save fuel, I still get **** MPG. Gonna go back to stock intake tmrw, if that doesn't fix anything then dealer.

 

[wharriso]

I always wondered about these replacement intakes, it seems to me that by definition your mileage will be worse. Think about it, isn't the whole idea to increase airflow? If that is the case, doesn't that mean the computer will in turn mix more fuel in with this increased air? After all, when you step on the gas, you are really not adding gas, you're adding air.

I pulled mine on my old car and I got a few additional MPG's.

Hey, I am no expert, please straighten me out if I am wrong.

 

[boominXplorer]

Out of curiosity did you pull the negative battery terminal off for 10 minutes after installing k&n?

 

[MikB]

I'm not sure about losing MPG because of this mod. I lost nothing on my Ex and in fact, gained a little. But, I suspect that the tune has more to do with it. The fact that you may get better airflow has nothing to do with lessening gas mileage and more to do with gaining MPG. It's not gained with your right foot as I suspect maybe the case here. MPG is done in cruise mode, not acceleration mode. More cruising, better MPG, more acceleration, bad MPG. See how that works?

 

[Odrapnew]

I always wondered about these replacement intakes, it seems to me that by definition your mileage will be worse. Think about it, isn't the whole idea to increase airflow? If that is the case, doesn't that mean the computer will in turn mix more fuel in with this increased air? After all, when you step on the gas, you are really not adding gas, you're adding air.

I pulled mine on my old car and I got a few additional MPG's.

Hey, I am no expert, please straighten me out if I am wrong.

These intakes have the ability to flow more air, but can/does your vehicle take advantage of it?
Stock intakes are more than adequate for normal driving(not full throttle acceleration) and cruising around. It takes the same amount of power to cruise @ 70mph regardless of intake.
Some vehicles can take advantage of a high flowing intake, but that's usually at high throttle inputs and high rpm.
And, on top of that, if you accelerate and drive the same way with a stock or aftermarket intake, your fuel mileage should not change... well, if you are full throttle all the time, you might see a difference.

 

[AFKNinja]

So it seems as if whatever the problem was is gone, I'm able to get into the low 20's with my MPG's again. I guess the computer may have needed some time to adjust to the change in air flow? Very odd, but everything is fine now so I'm content. Thanks for all the reply's everyone.