The guage i use (db), is setup for the brown wire, so the brown wire is tied up, unless i could splice it and run it to the AC wires too?

 

Im wondering this too!

I want to log some then send it over to my tuner..

Awesome write-up!

 

It will log all of the information and save it accordingly. Your tuner will have to program his custom data view with the information provided above to view it. The data is there, but the tuner must input the equation/parameters to view it.

 

Alright, thanks.

I have some problems tough, when I type in "gain" at 0.05896 it will change itself to 5896, the decimal wont stay. The same with "offset"..?

 

Ok this is what it looks like when I first put in the values:




Then I click OK and get ****ed up readings I think, because when I open it up again it looks like this:



The decimals are all gone in gain and offset

 

Any thoughts on how to do the same with a 165 or 730 OBD1 ECM ?

 

I am using this data to compose a similar setup with my FJO wideband controler and datamaster. I've run into a question when calculating the linear equation. You say that with the LC-1 the equation is AFR=3.008V+7.35.

My question is were did you sumize the 3.008 from? My FJO goes from 10.0 AFR to 20.0 AFR thus I am trying to calculate the new equation. If I know were you came up with the 3.0008 I can complete the equation. If 3.008 holds true in factoring in the correct gain and offset for both controlers I can then use the given equation.

Thanks for your input and GREAT thread!

Edit: Ahh yes my output analog signal will be from 0V to 5V.

Edit: I'm also having trouble figuring out how you derived .0196 from the equation AFR=3.008V+7.35. Could you please explain. THANKS.

 

that's the slope of the regression line.

Slope = rise/run
Slope = (change in AFR)/(change in voltage) = 10/5 = 2

You can use 2 for your slope and 10 for the intercept (2v+10). The EXACT relationship should be in teh FJO literature or by contacting the company.

the "intercept" is the AFR indicated by 0 volts, the slope will be the gain in AFR per volt (which I estimated around 2 above).

 

Ok so my equation looks like this: 2V+10. That makes sense. So my offset is 10 but to solve for the correct gain input I need to find out how you derived .0196 from your equation AFR=3.008V+7.35. This is how you came up with your gain.

"Replacing V with the integer above, we get AFR=(3.008*0.0196)*N + 7.35 which equals AFR=0.05896*N + 7.35 ; this function will convert raw data N to AFR."

How do I come up with my ".0196", figuratively speaking, to complete my equation for my final gain input into datamaster. Or are you stating that my gain is in fact right in front of my face: "2"?

 

what If we still use the AC.. I asume we cant use that wire, Other option?..

I dont use EGR anymore, is there a EGR position sensor I can use?

 

this was intended for tuning only. when your tuning dont use your ac. when your not tuing plug it back in..

 

I wired up a simple DPST switch inline with the AC input. One position connects the the AC sensor to the PCM, the other position is the WBO2 input instead.

One note... if you're tuning the idle speed or cyclinder distribution do NOT use the WBO2 (or the AC) as the PCM will adapt for the extra load the aC is seeing... obviously if the AC isn't on this can cause minor rpm fluctuations that affects your idle speed.

Also, if you use a switch like I did, make sure you twist and solder the wires firmly, then paint the contacts with liquid insulation (rubber stuff you can get a Lowe's Hardware or the like) then wrap it in 3M Electrical Tape... keeping the contacts dry will prevent corrosion and help this be a nice long-term installation.


As for the 0.0196 question, that came from the idea of displaying AFR in the AC field in datamaster. I don't use datamaster myself, so I've never had to do it, but that factor is used to "adjust" your voltage to show up in the PSI reading of AC. Take the 2, multiply by 0.0196 and you'll get the actual factor you want to use in datamaster... this way the AC Pressure field will display your AFR directly as a PSI (though the decimal will be 1 off... like XXx.x instead of XX.xx, but that's as close as you'll get by using datamaster).

 

Excellent! Thank you for your help. Now I don't have to run seperate laptops for each program in the car.

Edit: So for folks using the FJO data input would be same as your's with the following exceptions(be sure that the volts for the Aux output are from 0v to 5v for the calculations to work correctly. Also the min and max AFR set to 10 and 20 respectively) :

Offset = 10
Gain = .0392

 

I DEFINATLY vote for this to be cleaned up and made a sticky.. GREAT info here that ALOT of people can use!

 

So I just need to look up which wire on the pressure sensor connector feeds the 5v signal into the PCM and connect that to my 0-5v out on the lc1 correct. Is that the only wire I need to tap into on the pressure sensor?

My LC1 has only 6 wires so I don't have an analog output ground like the LC1's with 7 wires.

If I can get this to work, this will help out my tuning capabilities alot!!!

Thanks everyone, good info!