89 t-bird poor idle and uses too much fuel

[joneser02]

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.

[flewthecoupe]

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.

[joneser02]

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.