warrusmc

After checking AutoMeters site I do not see an output with a 0-4v or 0-5v signal. You need this type of output from your gauge to do this mod. I would check with AutoMeter directly to see if there is a way to get this output from your gauge.

kyoo

iTrader: (29)

just to reiterate, ams did whatever was listed in the first post and now my autometer is getting read by evoscan through tactrix! i love it. changed the formula since my low and high readings are 10 and 16 respectively. matches my autometer boost gauge so i am happy. they'll be taking care of my CEL through tephramod or whatever as well.

in short: post #1 method for logging autometer works - thanks again!

sleeper1

hi guys,
this formula 10+(16-10)*x/204 doesnt read right on evoscan properly for me i`m afraid the autometer is spliced into the rear o2 loom and reads fine through the ecu but to get it to read 14.7 at idle/cruising i have to use 10+(16-10)*x/185. this puts the afr at about 10.2ish under full load when it should be reading 11.4 (confirmed).

also if i negative back to the ecu through the loop and not to chassis ground i get a low voltage cel, i assume this is because the ecu is expecting 5 volts?

am i doing something wrong? as i read on here it should work perfectly.

thank you.

CavinessEVO9

Try this, just figured it out today for my AEM uego which is a 0-5V signal.
10+1.960784(.01960784*x)
I'm almost positive that should work for you as well.

sleeper1

the autometer is 0-4v signal though?

CavinessEVO9

so try this one and let me know if it works, should be pretty close if not right on.
10+2.35925299*(0.01960784*x)

sleeper1

umm, a log of about 144 on idle, thats 144, not 14.4, lol

i`ve also tried this one (X*((0.000033118*X)+0.0403455)+8, same result, a afr of about 147, so i put /10 on the end to try to divide the reading by a factor of 10, no change

i shall persevere

CavinessEVO9

Log the oxygen sensor #2 (voltage) with evo scan. Should read about 1.99 or 2 volts when at 14.7 on the gage. If so, turn the car off to stop the engine and then back to the on/acc so that your gage will come on and continue to read different voltages as the meter slowly maxes out to lean. Write a few vales down. And post them here for me. Since it's a 0-4 v gage, I'm assuming the voltage at 14.7 should read about 2 volts. Post them up here for me and I'll get you an equation. Should look like this
14.7=1.99 V
15.4=2.4
16.2=3.0
Something along these lines.

sleeper1

yeah so far the only formula that reads the same as the gauge face at idle is 10+(16-10)*x/170/180 ish got me beat which according to merlin, my resident electrical engineer is similar to yours is just a a longer equation.

this /170 has no correlation with the original equation on this thread for a 0-4v spread, that final number was 204 which is 255 divided by 5 and multiplied by 4, ie 204

should work, but not

170+ish gives me the gauge face readings which fluctuates from about 14.8 to 15.

so, meh, u want me to send u a .csv but failing miracles it wont help.

it isnt that easy, theres an offset somewhere, maybe in the ecu.

CavinessEVO9

I think you may be putting the equations in wrong somehow or maybe just a typo. the figure "x" should only range from 1 to 255. which in any of those equations, wouldnt give a reading of 140 something. You should make sure that evoscan is making the right request which is 3C for the rear O2. And I think that also changes with the market of the car USDM vs AUDM or JDM. Just an idea to check.

CavinessEVO9

From what I've read, all the uegos use a linear equation to covert voltage to thier readings. So with that in mind, my last equation for a 0-4V gage should've been

10+2.35925299(0.01960784*x)

and a 0-5V should be

10+1.960784(.01960784*x)

The numbers you were getting are due to something else with in the car being setup wrong or that EVOSCAN is making a wrong request. I know for USDM that the request for rear O2 is 3C. So maybe its just as simple as a different request for your market model.

sleeper1

thanks for the reply, i`ll try those out, and yeah, the request is 3C.

from autometer instruction .pdf

CavinessEVO9

If that doesn't work for you, then make a new request on evoscan for the rear o2 (3C)and just set the equation to "x" and see what the ecu signal is actually giving you. It's "should be" a number between 1 and 255. Also, you should be running the tephra mod so you don't get a CEL and you can't use the rear O2 patch with the car set up this way. Hope this gets us in the right direction