Ok, it didn't break my wideband, but I have a 243/250 .611" cam in my car and I'm trying to do an AutoVE tune on it right now. The problem with it is that when I turn the ignition on (car not running) and let the WB warm up, it displays the AFR correctly (20.9) on my XD-1. When I start the car up, the wideband basically shuts off if that's even possible. My XD-1 displays bars where the AFR should be, and EFILive doesn't get the correct readings. My BEN values are all 1.28 plus or minus .01, or when the MAP reading goes up they are all 1.13 plus or minus a few hundredths. Basically the LC-1 is sending a constant voltage to EFILive.

Has anyone had this problem before? How do I fix it? I just need to get this working so I can dial in my VE table. The idle is already close enough. This is my last big hurdle.

 

Sorry forgot to mention a few details:

a) the wideband was working perfectly before the cam. I did the AutoVE tune a few times (stock, stock + headers, headers + TB) and it worked fine.

b) the first time I started up the car with the cam the car was really loping hard and the wideband would read an AFR after each lope, then an air pocket would hit and it would read really lean. The second time it stopped reading all together.

c) the 02 sensor is installed in one branch of the y-pipe so it doesn't get exhaust pulses from both banks.

d) I originally left the EFILIve file "SAE_Generic.txt" alone, but tried to change the V settings for an LC-1 from 0-5 to .88333 to 4.217 in order to reflect what the LC-1 was programmed to put out. Is this incorrect?

 

Sounds like the file change might have messed something up or you have an analog signal wire that has come loose. I would try reloading the SAE_Generic.txt file to see if you created a problem there. If that is not it, check the wiring.

The way I set my LM-1 up is to select the PLX pid and then set up the LM-1 analog output voltage to match the PLX pid voltage - it works great.

 

I'm suspicious that doing a "free air cal" in the pipe,
has the thing exposed to something other than
what it thinks it's supposed to be getting. If the unit
is calibrated to spent exhaust residue it may whack
the reading. I doubt the exhaust has the oxygen
content of free air. I don't know if the LC-1 has an
auto-cal like the LM-1 but I do know, that running
an in-pipe cal on my LM-1 gave me some bent readings
the one time I did it.

Sensors can go bad, they can be damaged by
condensation (crack the ceramic when you put heat
and water together) or fouled. If the tune has been
really messed up by the cam, maybe it's just coated
with soot or something.

It'd set you back about $50 for another sensor, to
find out. If the unit has a calibration function you
might want to pull the sensor, let it calibrate in the
specified conditions and reinstall before you spend
the dough.

I don' tknow how FlashScan treats the wideband
inputs, but you might want to look at raw voltages
as well as AFR / fuel air multiplier and see what the
unit is sending.

 

Maybe I messed it up in the calibration. The XD-1 is a A/F gauge made by Innovate specifically to hook up to an LC-1 or LM-1. It has a calibration button on it so you can do a free air calibration while the sensor is in the pipe. Innovate recommends that you do it after the car has been sitting 6-7 hours. I did mine after it had sat overnight, but maybe it's still messed up. I haven't tried to use it since I last did an in-pipe free air.

The strange thing is that it shows the correct AFR before the car starts (20.9). If it were miscalibrated I would think that it would show something different. I guess tomorrow what I'll do is hook the LC-1 directly up to the laptop, instead of indirectly through EFILive, and also measure the analog out wires directly with a DMM. I'll also pull the sensor unit and see if it's fouled in any way.

 

I would unscrew the O2 sensor and let it hang outside of the exhaust with the ignition in the run position for 2~3 minutes. Then do a free air calibration and reinstall the O2. If that doesn't fix the problem, double (triple) check all of your wiring. If you're still having troubles after that, it may be time for a new sensor.

 

That's probably the highest it will read, so I wouldn't assume that it's calibrated correctly based on that.

How close is your WB to the exhaust port? I was thinking that you might actually be too close to read a lopey cam correctly, but every case seems different.

Have you tried an alternate power source like another car battery and have the WB operate independently of you starting your car? just to eliminate a power supply issue.

 

Now that I think about it, maybe you're right about the calibration. I just remember from mixing Nitrox for use with scuba diving that air is composed of 20.9% o2. I guess I just got confused and thought it was reading the "correct" AFR.

Anyways, the sensor is located ~1.5' back from the front o2 sensor.

About the power supply, I was actually thinking the same thing. I took switched power and heater grounds from a rear o2 sensor harness and deleted the codes for my rear o2's. The wideband worked perfectly fine with this setup before, but maybe something happened where this doesn't work once the ignition is on anymore. I might just probe the points of my inline fuse with a DMM though to see if it's getting the voltage. If it is I'll test the current.

---

Also, does anyone know about the "SAE_generic.txt" question? It has a table with something like the following:

10-20 AFR
0-5 V

Not having a knowledge of how EFILive works, but having been a programmer for years I'm assuming that this tells Live that the AFR varies linearly from 10 to 20 in direct proportion to a voltage reading of 0-5V. Do I therefore need to input the values you program the LC-1 with (.88333-4.217V) or do you leave it as 0-5V? The Live tutorial says you "may need to change you settings to reflect those of your wideband" but is not more specific.

 

The thing with these "closed loop" calibrations is, it'll
mess the sensor electronics around until it gets the
20.9 value, that's its goal, embedding the assumption
about the surrounding gas. But if it seeks to that 20.9
in (say) a 5%-oxygen in-pipe environment, you're now
"calibrated" to way-the-hell-off. It could take a bugger
long time for head-end exhaust to re-reach atmospheric
balance, by diffusion up the pipe from the exhaust tips.

Better 5 minutes with the wrench, than 6-7 hours to
"maybe right enough"....

 

In sae_generic.txt, isn't this the calculated pid for the PLX WBO2...?

Do one of the following:

a. Check that stock sae_generic.txt already contains a pid for the LM-1.

b. edit the calculated pid in sae_generic.txt to match your LC-1 (or create a new pid in calc_pids.txt):
first calculate: slope = (AFR2 - AFR1)/(V2 - V1)
then set pid to: ({EXT.AD1} - V1).slope + AFR1

c. program your LC-1 to match the calculated pid you're using (but note that this may not match your LM-1 gauge):
0V is AFR 10, 5V is AFR 20.

 

What Version EFILive are you using? I know the earlier version needed some input for the LC-1 but the latest version 7.3.1 already has the PIDS for the LC-1.

I wouls also do a free air cal with the WB hanging out of the pipe.

Good luck.

Bill

 

Yeah exactly. I've often wondered if I could just stick my shop vac up to the tailpipe, and open the throttle to speed up the process.
hehe being lazy.
Maybe I'll try it one day.

 

That's not lazy....that's using your head!! Great idea.

 

OK guys I think i figured it out. I took the sensor out of the y-pipe and found a layer of soot on it. Hmmm guess I'm running a little too rich. I cleaned it off and let the sensor dangle in free air. I then performed a free air calibration. I put it back in the pipe and took a look at how the LC-1 was programmed to make sure it was OK. Well anyways everything looks normal and I'm about to close out of LM Programmer when I notice my "Stoich AFR" is set to custom. I look at the value and it's something like 73:1. The LC-1 thought that anything less than 73:1 AFR was leaner than stoich and hence **** a brick. Needless to say I reset it back to 14.63:1.

Anyways I went for my test voyage (I'm trying to do an AutoVE tune) and the needle of both my XD-1 and laptop gauge are pegged at 7.4 (the lowest AFR it displays) for 90% of the ride. When I let off the throttle and DFCO (which I thought I disabled?) should come on the wideband reacted exactly how it should, and it gave me a few other clues it was working somewhat correctly. My question is now is my AFR really at 7.4:1 or is my sensor clogged up from my previous go around? I would think it's reading the actual AFR because of the soot I found on my sensor, but at the same time my exhaust doesn't smell of gasoline at all. I would think running that rich I'd damn near see gasoline dripping out of my tips.

 

I had a similar problem after a freecal. Turned out with the LC1 once you cal you should power cycle it before starting otherwise it read high.
So cal, then turn off power wait 30sec or so then power back on. Then it works fine in the exhaust. But I usually cal after 2 days of the car sitting idle just to make sure the pipe is clear of other smelly stuff.

 

That's a great idea, thanks.

 

Is that after warm-up?

When my LC1 warms up it shows 0v on all guages until it's complete (0v=20 something AFR)

 

Check the cable for continuity , when mine was doing that **** I had a bad solder joint in there.