First question for a 1998 dodge durango what is the signal wire from the o2 sensor leading into the computer. I have a air/fuel ratio guage and all it does is jump from lean to rich none stop im guessing i have it hooked up to the wrong wire. And my second question is i have a vavuum guage also and at idle itll read 20 and at gaining speeds it drops to 0 which is normal but sometimes it reads poor vacuum what can e causing this. Thank you

 

When do you get the poor vacuum reading? And what are you trying to do with the o2 sensor's?

 

The O2 sensors have, heat and readout going to the PCM.

Check your vacuum lines. Also there is a check valve right at the brake booster (where the main line plug in) that might need replaced. The second is inline and I think is at the main switch.

 

Im trying to hookup a air fuel ratio guage and the green wire onthe guage i have to hook it up to the wire that gives the conputer the signal from the o2 sensor and i mostly have bad vacuym when im drivin