I have an ls6 intake on my 99 trans am. The vacuum line that goes from the front to back (Intake Pulls Vacuum I believe). That hose where is coming off the intake behind the throttlebody is colapsed and has the Dry rot looking effect to it. How important is this to change? How hard?

 

That will cause a vacuum leak and should be replaced.

Are you talking about the short piece if 3/8 hose that connects the inline PCV valve to the intake manifold? If you look closely you will see the short piece oh hose still connected to the intake manifold. The factory one eventually got a hole in it and I just replaced it with a new piece of hose.

 

I’d replace it sooner rather than later. I had a similar issue on my LS1, and a bad vacuum line caused all sorts of weird idle problems and even threw a code once. It’s not super hard to fix—you’ll just need some good vacuum hose and maybe a pair of pliers to pull the old one off. Depending on how tight the space is, you might have to take off the throttle body to reach it, but overall it’s a pretty simple job and worth the peace of mind.