Intake ?

[jeeppowermj]

Im in the process of building a cold air intake for my 88 MJ. I took the old airbox and everything out. I noticed that there is a hose going from the exhaust manifold to the beginning of the intake(right by the headlight). It looks like a dryer vent hose but it is only like 1.5-2 inches around. What is it and do I need it?

 

[BIGSLVRXJ]

That is a hose to warm the air that goes in to the air box. It takes the heat off the exhaust manifold and shoots a little bit into the incoming air. I have had mine off for a year now and have an airtube, and I have only noticed positive results. I'm sure other people can add to this if you want to know more about it.

 

[jeeppowermj]

What did you do with the hose? Just pinch it shut?

 

[Slip Kid]

Take it off. they say it helps in the winter to warm up faster. but it's not doing any good if you have an airtube. the vac tubes asociated with it can go to

 

[jeeppowermj]

I just took it off like you recomended. Man that cold air intake sounds cool, It makes it run a lot smoother too.

 

[Dr. Dyno]

That is a hose to warm the air that goes in to the air box. It takes the heat off the exhaust manifold and shoots a little bit into the incoming air.

Yup,that's exactly what it's for and it's totally unnecessary on a multipoint EFI engine. It was only necessary in the old days when engines were carbed to prevent the carbs from icing up on cold winter days.

 

[MachineMan]

Yep, take it off. Although depending on where you live taking it off could cause you to fail the visual part of the smog inspection.

More info:
http://www.4x4trailhunters.com/article.php?id=16