Anyone Fussed Over That Airbox Thing?

[Matts 850 GLT]

Hi

I was replacing my airfilter (yes I still haven't gone the KN route yet) and found the airbox flap to be closed.

Took out my whole airbox and stuck it in the house and the flap never opened. Must be stuck shut.

How do you alter the spring loaded setting - how does it move??

Outside temp 45F so is this too cold for it to open?

Matt

[Guest AlvinL]

Well, it should be open (or closed depending on how you look at it) while the engine is cold and when it's cold out to allow warm air surrounding the exhaust manifold to come in to the airbox but as the air warms up, the spring reacts and partially close the door to provide the appropriate air temperature mix. Perhaps you could investigate if it's working ok.

However, some have totally disabled this thing to always stay open to always have cold air come in.

[icelandic]

Matts, that flap is activated by something called wax capsule, which looks like a small hydraulic cylinder. Over time, the "wax element" in it will leak out and the flap will remain in the hot air only position. Consequences are:

1- Engine will knock at light loads up to 2k rpm.

2- Mileage will decrease between 5 and 10%

3- power output will be lower, perhaps around 15 hp

4- the full time hot air admission will cause your MAF sensor to fail.

I live in a hot climate so I simply removed the mechanism and screwed the flap to one side of the housing so that I have only cold air admission. As you are in a colder climate, you may experience bad engine performance while cold if you do it.

So I advice you to replace the mechanism (the wax capsule). Once you do it, put the unit in the refrigerator and see if it closes. Then leave it at room temperature to see if it opens.

It is amazing how such a small and often neglected part can have so many bad and noticeable consequences.

Good Luck

Luis

[Guest Guest]

Matts, that flap is activated by something called wax capsule, which looks like a small hydraulic cylinder. Over time, the "wax element" in it will leak out and the flap will remain in the hot air only position. Consequences are:

1- Engine will knock at light loads up to 2k rpm.

2- Mileage will decrease between 5 and 10%

3- power output will be lower, perhaps around 15 hp

4- the full time hot air admission will cause your MAF sensor to fail.

I live in a hot climate so I simply removed the mechanism and screwed the flap to one side of the housing so that I have only cold air admission. As you are in a colder climate, you may experience bad engine performance while cold if you do it.

So I advice you to replace the mechanism (the wax capsule). Once you do it, put the unit in the refrigerator and see if it closes. Then leave it at room temperature to see if it opens.

It is amazing how such a small and often neglected part can have so many bad and noticeable consequences.

Good Luck

Luis

I live in a cold climate and have done what Lius has done,

screwed the flap to have cold air all the time.

I have noticed zero performane effects in many many

thousands of miles with this airbox mod.