I have a 88 Cherokee and bought the rusty's intake and it says to get rid of the vacuum line but it come off the intake manifold and is hissing what should I do it seems to idle better with it off should I cap it off?

 

When you plug it, does it run rough for a second and then even out? if so it is best to plug it.

 

If not, go to a parts store and by a small cone filter and use that to cap it off.

 

i just capped mine off...thats what the instructions said

 

No I am currently getting horrible gas mileage so by taking that vacuum line off it leans out the motor but I think I will just cap it off

 

LOL how long have you had a Jeep? Just kidding, Bad gas mileage goes with big tires and low gears and a 4.? I6. Capping/Plugging the vac line is always the smart move. Good luck.