tbi problems?

Hi all, I have an 88 iroc 305 tbi auto. I have several "symptoms" not sure if it is many things or just one. It does not idle when cold, after warming up it will idle high (around 750 in park). It accelerates somewhat ok (slow and a little rough). It uses a horrible amount of fuel to the point you can smell it.

I have replaced the fuel pressure regulator, no change.
It has the AIR system partially dismantled and the cat has been hollowed out and reinstalled.
Thought about changing it to a carb but I read other posts advising against it. Any suggestions where I should start? HEEEELLLLLPPPPP!!!!:crying:
Thanks< Kris

I'd start with the coolant temp sensor, it's cheap and very dtrimental to fuel mix and seldom sets a code.

THAT MADE A HUGE DIFFERENCE, got a lot to learn about tbi. Thanks for the help.
Kris