Car sputters and tranny doesn't shift

Watch the video: http://s54.photobucket.com/albums/g117/DynographK/?action=view&current=camaro_sick.flv

I heard no sputtering in your video, nor did I see anything from the tach that suggested sputtering. HOWEVER! I did see your oil pressure gauge needle was all over the place and from outside (when you let the engine idle down) it sounded like a pretty large vacuum leak.
Transmission??? If this is the 87 IROC in your sig, then it is a 700R4 and the nonshifting is a mechanical problem. Either a broken shifter cable or broken transmission.

Oh, and your engine and engine bay are very dirty. All of that dirt will make the engine hold heat.

I heard no sputtering in your video, nor did I see anything from the tach that suggested sputtering. HOWEVER! I did see your oil pressure gauge needle was all over the place and from outside (when you let the engine idle down) it sounded like a pretty large vacuum leak.
Transmission??? If this is the 87 IROC in your sig, then it is a 700R4 and the nonshifting is a mechanical problem. Either a broken shifter cable or broken transmission.

Oh, and your engine and engine bay are very dirty. All of that dirt will make the engine hold heat.

It can't be. I replaced the transmission with a rebuilt one and I got the same symptoms afterward.

So maybe it's ALL the vacuum leak's fault? How do I go about fixing this?

It can't be. I replaced the transmission with a rebuilt one and I got the same symptoms afterward.

So maybe it's ALL the vacuum leak's fault? How do I go about fixing this?
Vacuum leak won't affect the transmission. The shift cable for the 700R4 can be broken internally and unless you know what to lok for you'd never notice it.

To find the vacuum leak...listen and follow your ears. Then when when you have it narrowed down to an area, carefully spray carb cleaner (with the straw) to the area you think it may be. When the idle of the engine changes abruptly, you've found the leak.

I found a whistling noise, it goes on and off and sounds like it's coming from a vacuum hose. My question is should I replace all the vacuum hoses since they're old? Do I not need a new catalytic converter if this is the main problem?

Also I was revving it up to 3k today and the rpms were dying when I had my foot on the accelerator.

I found a whistling noise, it goes on and off and sounds like it's coming from a vacuum hose. My question is should I replace all the vacuum hoses since they're old? Do I not need a new catalytic converter if this is the main problem?

Also I was revving it up to 3k today and the rpms were dying when I had my foot on the accelerator.
If in doubt, yes, change all of the vacuum hoses (there aren't that many).
To check the cat converter, get the engine hot (drive it ariund the block a couple times) then park it somewhere fairly dark and look under the car atthe converter, if it is glowing, it is plugged and needs to be replaced.