F-body help!

OK, I know this is the Camaro forum, but I'm also posting the question in the Firebird forum. I need double the brainpower on this one because I'm stuck. I have an 89 Firebird Formula 350 with automatic trans. :grinyes:
Symptoms:
Car idles very rough. Enough to vibrate the steering wheel, mirrors, and door handle components.
Car will not go over 3000 rpms even flooring it (in gear, or in neutral).
Car must warm up for at least 5 minute before putting it into reverse or drive, or the rpms drop until the car dies.
Even after warm up, the rpms drop very low when shifting into drive or reverse.
Not enough power to burn out now. :crying:
Once driving, car will not accelerate quickly, take offs from a stop are very slow to reach even 40 mph.
When driving and accelerator floored, engine sounds like it's constipated (makes strong noise, but and barely moves).
Car smells like it's running rich.

Things I've done for it:
Replaced MAF sensor in response to error code 33.
Replaced old exhaust with 2 new hi-flo cats and Dynomax cat-back system.

I've been told I may have a loss of vacuum, but I'm not sure how to test this, or even anything about vacuum. I've followed the vacuum line diagrams in Chilton's, but I didn't see anything unusual, and I can't see the area around the EGR valve.
I'm also thinking it could be an O2 sensor problem, but I'm not getting an error code for this. Or, what about a timing problem?

Any ideas? Is there a vacuum pressure gauge I can buy? Should I pull the O2 sensor?
Any help would be appreciated guys. Thanks in advance!

First simple thing to check is the coolant temp sensor. It is located on the front of the intake manifold, it is the smaller of the 2 things screwed in there.
Next would be a full tune up, plugs, wires, rotor, cap and O2 sensor.

And...yes...timing :smooch:

What are yalls preference on plugs? I was thinking ACDelco Rapid Fires over Bosch platinum.

Sounds liek it could be your cat(s)

Just use the factory specified plugs. The high dollar plugs don't do a damn thing for these cars, just makes the owner poorer.

Sounds liek it could be your cat(s)

I thought it was collapsed cats too at first, but I've already replaced the cats with 2 hi-flo ones.

As for the plugs, thank for the heads up Morley.

ah, missed that part. oops.