It seems to me that having a different reading between a wideband gauge and tunerstudio is a common issue. Question is, what is the acceptable limit? My MTX-L has been reading about .7 - 1.0 richer than it reads in TS preventing me from doing any real tuning, so I rerouted the ground wires. Tried about 4 different places and finally settled on the one I have now that only has me about .3 richer. It's a lot closer, but I would prefer it to be dead on.

Any suggestions?

 

Have you tried running a wire between the two different grounds (grounding them together)?

 

Yeah, I've tried both. No measureable difference between the 2 ways of wiring it. I'm still off about .2 to .3 from the TS readings. Currently they are both soldered to a ring terminal and bolted to an unused bolt on the firewall. So far it's given me the best results.

 

I took several measurements of voltage at the MTX-L, and the PNP. At 22.3 (fresh air) the PNP read 5.09vdc at the connection while the MTX-L read 4.98vdc. I changed the AFR calibration from LC-1 Default and used the custom linear wideband setting, changing the points according to the offset in voltage. Works like a champ now, and reads steady from the gauge to tunerstudio.

Thanks goes to Braineack for the guidance!