Herm

1993 LS400 97,000 miles California car. While troubleshooting another problem I looked at signals VF1 and VF2 on the underhood diagnostic connector DLC1 with an oscilliscope. I was suprised that they appeared somewhat different. They both varied between about the same dc voltage however one had a triangular waveform superimposed on top and the other had a sort of a square wave with sloped top and bottom. I was not able to find much info on these signals, the service manual calls for looking at them with a voltmeter. Does anyone know why they are different and/or have further information about them ? The oxygen sensor signals OX1 and OX2 are identical. All I could find about VF1 and VF2 is that one is a left bank mixutre "feedback" signal and one is a right bank mixture "feedback" signal. I would think the waveforms should be similar. Have not noticed any performance problems and have no error codes. THANKS - Herm New Jersey