So I am pretty sure I have a vacuum leak on my 97, but I cannot find it. My vehicle idles a little rough, and on the highway I can hear the vacuum leak, however it quiets down once I slow down. On top of that my lines have never been replaced and have heavy deterioration on all the elbows and connectors.
The plan is to replace all my oem hard lines with generic hoses from napa. I will buy vacuum Ts and PCV valves as well. Since I am replacing the hard lines with hose, will I still need rubber elbows? I don't see how I can connect flexible hose to an elbow. Maybe with something like this?
Any tips are appreciated, since I'm going into this a little blind.

EDIT: Are the PCV valves different on a 97? I ordered two of these, but I think it may only fit the rear. I think I may need one of these for the front, but I don't know if this one will work.

 

The rear one has a metered orifice since it's connected to the intake manifold. It draws fumes from the engine and sends it to the intake to get burned during combustion. The front one does not since it's connected to the aircleaner. It delivers fresh, filtered air to replace the air drawn out by the rear one.

So front and rear may look the same but are not. You need both.

 

Thanks. I ordered this one, I'm pretty sure it will fit. Napa says it won't, but amazon says it will fit 4.0 Jeeps

https://www.napaonline.com/en/p/NOE6301078