General 1g plx wideband and logging on data logger?

[dnhieu]

alright i have been searching for the past 2 days on this info. im wanting to log my plx m-300 on my data logger but from what i read my wideband readings will be incorrect if im trying to log it through my egrt. does anyone have experience with this? from what i understand i can wire in a 6 ohm resisitor somewhere and it will level out the readings.

thanks in advance tuners
david

 

[GVR4592]

It depends on what input you are using.

 

[dnhieu]

It depends on what input you are using.

first off thanks for the help man...

actually i am clueless on where to start...i guess i can start by telling you what im wanting to do. i really just want to beable to log my plx wideband on my palm pilot BUT also leave my options open for future plans of DSM link. so i guess what im saying is im willing to do whatever it takes to do that. maybe you can inform me of what some of my options are???

thanks again
david

 

[GVR4592]

Dsmlink users can lock the Baro and IAT inputs when they are using the MAFT. This allows you to use both of them for datalogging. I don't see why you couldn't do that without Dsmlink, but I don't know for sure.

You can't use the EGR temp input, that's the one that throws the scaling way off with a PLX wideband.

I'll do some research and see what I can find about using the Baro and IAT inputs.

 

[dnhieu]

thanks man. i think earlier today i read one of your threads saying i CAN use the egrt input if i wire a 6 ohm resistor in. can this still be done?

 

[dnhieu]

also i will be getting rid of the gm maft translator for the 2g mass, chip, and safc combo untill i get dsm link. so lets just say thats my setup...

 

[GVR4592]

Well you're kinda screwed then. The newest version of Dsmlink, might have another available input for you to use, but that's not expected for a while.

You're only other option is to have a buffer circuit built by somebody with the knowledge to do so.

 

[dnhieu]

buffer circuit? i know some one very smart with this kind of stuff. would it be possible for someone like you and me to make one? is there any way i can buy one and wire it in place?

 

[GVR4592]

buffer circuit? i know some one very smart with this kind of stuff. would it be possible for someone like you and me to make one? is there any way i can buy one and wire it in place?

Mine was built by an electronics guy, he said I wouldn't be able build it unless I was very good with a soldering iron and small parts. I can get you the part number and explain the wiring but that's about all I can do, I don't really know much about it.

 

[GVR4592]

It's a Texas Instruments rail to rail op-amp P/N TLV2371IDBVR. You can get them from digi-key for a couple dollars.

 

[dnhieu]

are you logging a plx wideband on your logger? if i get this "buffer circuit" will i just beable to wire it up and it will work? or will there be more moding needing to be dont to the texas instrument "buffer circuit"? a wiring diagram with the buffer ciruit installed would REALLY help!!!

thanks again
david

 

[GVR4592]

I used it for a while when I had Dsmlink, but I've been using AEM for about a year now so it's not installed anymore. I don't have a wiring diagram, but if you can find somebody to build it for you they'll be able to help you with that part. It's pretty simple though, it needs +5v, ground, wideband in and wideband out. So 4 connections at the ecu and thats it.

 

[dnhieu]

well i hope this doesnt sound dumb but can you explain what this buffer actually does? i have never herd of it before....

 

[GVR4592]

I dont really know what it does. I THINK it lowers the impedance of the plx output so it more closely matches the impedance of the ecu input.

 

[dnhieu]

do you still have yours? i would be willing to buy it if you still do...

 

[gotlag]

thanks man. i think earlier today i read one of your threads saying i CAN use the egrt input if i wire a 6 ohm resistor in. can this still be done?

Actually it was saying the issue with the 1G is that circuit is 6ohm to ground and the 2g was ok because it was 100om to ground.

I understand what the cuircuit is doing and that the PLX is high impedance. i will see what I can do to help David, and when fugure out we will be sure to post the fix for others.

 

[gotlag]

Hopefully another person can chiime in here. Is there any reason a resistor of a 2k or 2.5k ohm couldn't be bridged from the signal wire to the ground to clean up the impedance issue here? Then It could be voltage scaled via the egt sensor???? Not to oversimplify it, but it seems that should provide the buffer???

 

[dnhieu]

Hopefully another person can chiime in here. Is there any reason a resistor of a 2k or 2.5k ohm couldn't be bridged from the signal wire to the ground to clean up the impedance issue here? Then It could be voltage scaled via the egt sensor???? Not to oversimplify it, but it seems that should provide the buffer???

by high inpediance do you guys mean that it puts out too much voltage so the readings would be off on the logger? if so then why wouldnt a inline resisitor chiime down the voltage to get it straight? i guess the problem would be finding the right resisitor so that the afr is correct right?