Zeitronix + SAFC2 Troubles

[480sx]

First time posting, although iv spent many hours of the last 3 mounths here. I recently installed the baseline Zeitronix setup, without the LCD, boost or EGT. Im also running SAFC2. For some reason, the RPM imput on the Zeitronix is going nuts. It reads accuratly at low rpms, under low throttle situations. However, when i get into high throttle, high boost it will jump from its true reading all the way to 15000's and everywhere inbetween. At first i thought that sharing the RPM imput splice to the ECU with the SAFC2 could possibly cuase the false readings. I respliced the yellow wire with the red stripe(pin3, RPM imput) so that the safc2 and the zeitronix tapped it at differnt locations, no change. Has anyone had a similar experiance? Btw, thanks for the HUGE base of knowledge thats kept here.

[Neejay]

Is there a possiblity that sharing the wire (Zeitronix + SAFC2) is a problem?

Have you tried having one OR the other wired, and not both at the same time?

Just taking a shot...

[480sx]

I went ahead and tried the zeitronix unit without SAFC2 and it worked fine. So its definitly the SAFC2 sending conflicting signals to the w02 controler. While thats fine and good, a wideband without tuning capability is...... Im not much of an electrical guru, does anyone have any ideas about how to solve this problem? Again this might sound dumb but.. Is there a way to make it so electricity only flows one way through the splice? I would think somthing like that could fix the problem.

[480sx]

Got it! A noisy ECU ground was the culprit. Both the SAFC2 and the zeitronix work like a charm.