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I got arournd to check to see why my VR analog input wasn't working anymore. I pulled the cover away from the ECU pulled the middle plug and turned the ignition switch on. I tested the ECU side of the plug with a multimeter where my wire connects to it and I was getting 2-3 volts and when the wideband was warmed up it read 5 volts.
I grabbed a wire with alligator clips on it and I reconnected my ATP input. Clicked atp in the ecu setup page and also clicked plx devices. Plugged the ECU back up turned the ecu back on and checked the voltage on the multimeter and the reading on the palm.
I was getting 13-14 afr's on the wideband for ATP and a steady 16 afr for VR. I connected them both at the same time just to test and my ATP is working, but not my VR. PLX devices where clicked for both inputs.
The VR input was working just a few days ago. Is it broken?
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I just got my ecu installed last night, ran a few small logs, everthing seems to work, I'll be installing a PLX SM-AFR and WB O2 sensor this weekend and will be using the vr input... I'll let you know how it works out!
Hmmm... I hooked up my plx over the weekend to the VR input and got the same thing?.... Started at like 15.88 or something and once it was all warmed up went to like 16 and stayed there flat...?
I'm going to look at it tonight or tomorrow?
I have only had one prob and the rx7 program had to reload settings from the ecu or something... lost my updated settings.. not that I had a lot...
I cannot confirm 100% if everthing is wired correctly, but I'm pretty sure...
PLX instructions say "If you plan to integrate the SM-AFR with stand alone engine management systems, piggy back systems, data loggers, or any other devices that utilize the two analog outputs, noise filtering capacitors must be installed near the application. The included capacitors filter out unwanted electrical noise produced from your vehicle's ignition and other onboard systems. This provides added signal integrity for more accurate, reliable, and consistent measurements. Any 0.1uF 50V ceramic capacitor will work."
It has a diagram w/ the cap installed between the GND and the WB 0-5V linear analog output.
With the input hi-z (i.e. not connected to anything) the value of it is "undefined". Basically the test you ran is invalid as the reading can be anything if there is nothing connected to it. There is nothing "pulling" the sense circuitry to any particular value, so it's just "floating" around. What you are seeing is probably an input filtering capacitor slowly charging up.
Kinda like gravity. On earth you are always pulled to down until something stops you. You know you will always be at that point. Now imagine going into space...no gravity, so there is nothing to pull you in any particular direction so your location at any particular point can be anywhere.
I have heard of a report or two (not Rtek related in particular) about PLX's output being a little weak compared to some other WB02 systems..
I would measure the PLX output and while measuring it, connect it to the Rtek input and see if there is any change in the voltage when you make the connection.
or if you see it floating when disconnected, you could try grounding the VR input and see if it drops to zero on the rtek? that way you would know if it is rtek or not
or if you see it floating when disconnected, you could try grounding the VR input and see if it drops to zero on the rtek? that way you would know if it is rtek or not
Good suggestion.
I also suggest using the "voltage" preset in the WB setup for testing so the reading on the Rtek can be easily matched to the volt meter.
Well.. hooked it up again, the exact same way as before. It works. It read a 12.5 - 13.6 AFR at idle. I think the PLX plug isn't getting a good connection to the ecu.
Initial test: The plx measured 5.0V on the meter.. hooked up to the RTEK ecu I showed 20.0 EGR.
Test after Install(hiding the box): Same as before... the 13.4 or whatever going up slowly.. jiggle the wire I got 18.9 or something (this was after a short idle time probably still had exhaust in the pipes).
Road testing tomorrow... But it worked just like it should! Yay!
I took it out for a spin last night, everything seems to be working correctly.
Except I logged a 12.9 afr at 9.2psi... yikes, and my boost gauge reads higher than what the logger says? I've seen it edge to 15... but the most I've logged is 10 or so...?
same problem i get.. above about 9-10 psi, the rtek starts reading about 2 psi lower than my boost gauge. I had the boost turned up to about 16 psi once, and the highest the log read was about 12.5 psi
i swapped my boost references and it seemed to fix the problem?? the rtek and boost gauge read nearly the same now.
this is wiht the boost sensor is connected to the bottom port at the front of the UIM, my gauge and boost controller are connected to the port on the passenger side of the LIM
Linear Mode
