89 t-bird poor idle and uses too much fuel

I have an 89 bird and it is running rough at idle and consuming way to much fuel. i had the codes checked and i found that 1: PFE/EPT/EVP below minimum voltage. 2: No EGO sensor switching detected. 3: air fuel mixture not within test range. I am unfamiliar with these sensors if any knows what is causing the problem based on this information it would be very helpful. thanks.

First things first, replace the O2 sensors if you haven't already. It is a good idea to replace them after 80,000 miles or so because the slowly go bad and don't read properly even thought they might not ever set a code. Next would be to replace the PFE sensor. I had an '88 with a bad PFE sensor and plugged cats and the car acted just as you describe.

thanks, i am going to replace the o2 sensors tommorow and if that doesn't fix it ill look into the pressure feedback sensor to. I have seen a lot of people say that sometimes the pfe vaccum line can crack causing the system to malfunction. ill look into that too.