Huge Offset problem w/ LC1, help!

[WS6Fury]

I've read 100's of posts on how to wire this thing up, and I used what was best available to me at the time for wiring and location.

I programmed the LC1 to output 3v. I checked the LC1 analog wires w/ voltage meter to confirm, and it read a range of 3-3.1v. I scan raw voltage in HPT and I get 1.382v!!!!!!

What is weird is when I first did this without forcing a volt output via LC1, I just logged raw volt output in hpt at 4.81v, and using voltmeter I read 4.95v using analog wires.

If I were to just use the PID for LC1 WB it reads approx 21.9 vs the Logworks reading of 20.9afr.

I dunno, maybe I've been fooling around too much on the TA and drained the batter too much and its throwing readings off now??

Here is my wiring scheme:
A. From the LC-1, these go to a square 4 pin stock O2 plug:
red = heater power -> NBO2 socket heater power = D
blue = heater ground -> NBO2 socket heater ground = C
yellow = analog out 1 -> NBO2 socket signal = B
green = analog ground -> NBO2 socket signal ground = A

B. Splice an extra green 6ft wire to the LC-1 green wire.
This is used in C. below.

C. From LC-1:
extra green wire -> Logger WBO2 gound
brown -> Logger WBO2 signal
black -> calibration
white -> system ground (goes to chassis ground)

Push button, goes between the black calibration wire and chassis ground where white wire is grounded. Same for anode.

[PurplePiss]

Do not power the LC-1 off of the car's O2's sensor. Run a separate power from the fuse box that is switched to the key. Also, run the blue ground wire back to the engine block.

[WS6Fury]

Do not power the LC-1 off of the car's O2's sensor. Run a separate power from the fuse box that is switched to the key. Also, run the blue ground wire back to the engine block.

Not sure how I can run a wire to the engine block and connect it. The longtubes are kinda in the way and will melt the wires. where in location on the block is good, and simplistic for a guy without a lift to connect to?

And which fuse block, engine, or inside the car? Or doesnt it matter?

[WS6Fury]

Not sure how I can run a wire to the engine block and connect it. The longtubes are kinda in the way and will melt the wires. where in location on the block is good, and simplistic for a guy without a lift to connect to?

And which fuse block, engine, or inside the car? Or doesnt it matter?

Ok, really weird. With the car and ign on, the LC1 afr reads 20.9. I found the right equation on the custom PID to get 20.9 afr to read in hpt scanner. I go to start the car, and boom, the AFR is completely off. LC1 read 15, HPT read 17, etc.

So i converted back to original numbers and while car idled I'm still within approx 0.4 afr between LC1 and HPT Scanner.

Dunno anymore, confused at this point and need some direction...

[PurplePiss]

You need to ground the blue wire to the block. There is either a ground strap somewhere or you can ground to the front of the passenger side head. there is a bolt there. For +12 switched, take that from the fuse box inside the car. The +12 that you are using from O2 sensor harness is not constant.

Opened LMProgrammer and set it to 2.5 volts/2.5 volts and 10/18 AFR. 1/6 of a second. Program. Close.
Now since its 0-5 volts, 10-18 afr, then at 2.5 volts it should be telling HPT its putting out a 14.0 afr. I opened the user configuration for the LC-1 while I wasn't scanning. You can't seem to open it while your scanning, but if you leave it open, you can change the equation in realtime.
So the equation has:

Volts/.625 + some #. Mine uses 10.07. Leave this window open, then click on the "VE - Wideband O2, AFR" histogram. Configure it to show 3 decimal places. Start the scanner. If your equation is correct, you should see the 1 cell populating with numbers near 14.000. The longer you let it run the more accurate since it is averaging. Now, at this point you could change the "+" value in the other window. In my example, if you changed the 10.07 to 8.00, you would immediately see the AFR drop. Stop the scanner and clear the histogram. Lets say you were pretty close to 14.000. Try 10.06 or 10.08 depending. Start the scanner again. This is all while you have the User config LC-1 still open mind you. It should now start showing you the average afr again and it should be closer or farther away. Each time, make a change, stop scanner, and restart it to see a new average. I got mine within a hunderedth or so. When you set the histogram back to show 1 decimal place, it should read rock steady at 14.0. Go back into LMProgrammer and set it to 0-5v, 10-18 afr.

[WS6Fury]

This is again very interesting, and thank you for the tip on hpt and lmprogrammer.

For entertainment, I went ahead without doing the rewiring first to see how far off I was on the afr. So, i went ahead and did like you said and put the volts on lmprogrammer at 2.5 and programmed. In hpt I have my afr range at 10-20 for now until I can get my afr more centered and accurate, so the number would be 0.5/10+ offset.

Anyway, I opened up the scanner and started scanning after I started the car, and my afr is reading a constant 12.7afr. I am assuming a 2.5v should command a 14.0afr?? I tried different volts in lmprogrammer while the car was started like you said, but it would not change the reading, it just stayed at 12.7afr, even after going up to 4v.

I changed everything back again, and it went back to within .4 of the actual afr I could read on logworks.

So something is really weird. I cannot believe I would be that far off (2afr when commanding 2.5v from lmprogrammer) when comparing to what i read on logworks vs hpt tuners shows me I'm only 0.4 afr off......

[WS6Fury]

Ok, problem solved finally.

I did like you said. First I did the ground the the block ribbon cable, which actually goes to the alternator which is of course mounted to the block.

Didn't make much if any difference in my readings. What did make a difference was disconnecting from the NB wire harness, and route straight to the fuse box in the car. Started it up, did the 10-18 range, and my total offset was -0.08. So the equation in hpt was volts/.625 +9.92.

So a hair higher yet than what you have at 10.07, but at the opposite real though, which is strange.... but it works.

Thanks for all the help!!

[PurplePiss]

Sounds like you got it. As long as your AFR in lmprogrammer is 10-18 and the range in hpt is .625 + something, your set. Now, follow the rest of that thread and set you decimal places to 3 and then keep restarting the scanner fresh until you get it as close as you can to 14.000. Then when you go back to 1 decimal place it should be rock steady at 14.0.

Once your up and running, drive down the road and see how close you are to 14.7 in CL when you all warmed up.

[kabbott]

Quick question guys, Are the v8's different from v6's in respect to factory o2 harness, i have been powering my LM-1 off of O2 harness without issue... or so i thought anyway.it's powered all the time and almost no offset, at least at idle.

[WS6Fury]

Sounds like you got it. As long as your AFR in lmprogrammer is 10-18 and the range in hpt is .625 + something, your set. Now, follow the rest of that thread and set you decimal places to 3 and then keep restarting the scanner fresh until you get it as close as you can to 14.000. Then when you go back to 1 decimal place it should be rock steady at 14.0.

Once your up and running, drive down the road and see how close you are to 14.7 in CL when you all warmed up.

Yup, got it pinned on 13.999-14.000. Did drive it around and watched the hpt afr vs Logworks afr and they both seemed to follow suit with eachother. Now I just gotta retweak my VE table again, and then move onto spark tuning, which I gotta figure out how to do...

[PurplePiss]

I would go out and cruise down the highway and see if you car is running close to 14.7. Did you set the output rate to 1/6?

[WS6Fury]

I would go out and cruise down the highway and see if you car is running close to 14.7. Did you set the output rate to 1/6?

yup, its on 1/6 rate. Little bit of massaging needed since the afr was slightly off, but now hovering around 14.7 in general.

[Zick]

Do not power the LC-1 off of the car's O2's sensor. Run a separate power from the fuse box that is switched to the key. Also, run the blue ground wire back to the engine block.

Why should you not use the existing O2 harness if its already there?

[PurplePiss]

Because on a GTO, they are pulsed and not constant. Not sure if all years or other cars are the same.

[Zick]

Because on a GTO, they are pulsed and not constant. Not sure if all years or other cars are the same.

Ah gotcha, because thats how mines been wired up and working fine for quite a while.

[WS6Fury]

Ah gotcha, because thats how mines been wired up and working fine for quite a while.

yeah, somehow on my 02 WS6 my O2 wire harness power out just didn't cut it. So with Purplepiss' help he suggested I just go straight to the fuse box. Fixed the issue.

[orange ss]

Opened LMProgrammer and set it to 2.5 volts/2.5 volts and 10/18 AFR. 1/6 of a second. Program. Close.
Now since its 0-5 volts, 10-18 afr, then at 2.5 volts it should be telling HPT its putting out a 14.0 afr. I opened the user configuration for the LC-1 while I wasn't scanning. You can't seem to open it while your scanning, but if you leave it open, you can change the equation in realtime.
So the equation has:

Volts/.625 + some #. Mine uses 10.07. Leave this window open, then click on the "VE - Wideband O2, AFR" histogram. Configure it to show 3 decimal places. Start the scanner. If your equation is correct, you should see the 1 cell populating with numbers near 14.000. The longer you let it run the more accurate since it is averaging. Now, at this point you could change the "+" value in the other window. In my example, if you changed the 10.07 to 8.00, you would immediately see the AFR drop. Stop the scanner and clear the histogram. Lets say you were pretty close to 14.000. Try 10.06 or 10.08 depending. Start the scanner again. This is all while you have the User config LC-1 still open mind you. It should now start showing you the average afr again and it should be closer or farther away. Each time, make a change, stop scanner, and restart it to see a new average. I got mine within a hunderedth or so. When you set the histogram back to show 1 decimal place, it should read rock steady at 14.0. Go back into LMProgrammer and set it to 0-5v, 10-18 afr.

tried this, output showing 2.43v, HPT showing 14.1-14.2 AFR...how can i fix this ?

[PurplePiss]

If you used .625 + 10.00 and your seeing that 14.1-14.2, you need to subtract .07 from 10.00 (2.5-2.43). If you leave the window open, you can see it start to pull the AFR down to 14.0. You need to restart the scanner because it averages the numbers and the longer you let it sit at 14.1, the longer it will take to see an effect of changing the offset value. Hope that makes sense.

I should also add, that once you feel you got it nailed, you should set the lmprogrammer to 0 volt / 0 volt, which should yield close to 10 AFR and 5v /5v should be 18 AFR. It will probably be off since it isn't linear. By setting it up at 2.5, you will be accurate near 14.0 AFR. I'm not sure how close it would then be when your doing WOT testing at 11,12,13 AFR.

There is another option in there to take data at each of the voltages and create a curve. Anyone tried doing that?

[orange ss]

was using 10.19

[PurplePiss]

So you would stop the scanner, clear it, then put in 10.12, restart and see how close it is to 14.0. As the sensor gets warm and cold it will fluctuate. But once you get it close, it will be spot on when you go to 1 decimal place.