PLEASE help with LM Programer
#21
Boost Czar
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It's a bad practice; really bad.
The sensor is supposed to be in "free-air" for the calibration. We are talking about an import device here that requires accuracy. The entire purpose of the free-air calibration is so the sensor knows what 20.2% oxygen content "feels" like. Remember, you're calibrating the sensor, it has no idea what-is-what unless you give it an absolute. Do you not zero your bathroom scale before you weigh your fat ***? Makes you feel better when you weigh 10 lbs "less." If you're not metering the atmosphere, then you're calibration will be incorrect.
I, unlike AFRman here, have no idea when my AFRs are correct unless my WB tells me. If I tell my WB that 14.7:1 AFR is actually 14.0:1 because there's residual gas floating around the pipes, then it'll always be incorrect. But how will I be the wiser?
Also, the proper procedure for the calibration is holding the button down for three seconds, then it starts to calibrate. IIRC, it calibrates for something like 5 seconds. That's kind of a long time to gamble that the ECU is cutting enough fuel long enough depending on the conditions. (Also have you ever turned off your car and continued to meter the exhaust? I betcha it doesn't read lean right away, nor after ten minutes)
Then after all that you're even supposed to power off the WB and turn it back on after 30 seconds to store the calibration into memory.
Why not get off your ***, unscrew the sensor and let the read the atmosphere, do the free-air calibration and screw it the **** back in. I tend not to try to gamble with things that need to be "accurate."
The sensor is supposed to be in "free-air" for the calibration. We are talking about an import device here that requires accuracy. The entire purpose of the free-air calibration is so the sensor knows what 20.2% oxygen content "feels" like. Remember, you're calibrating the sensor, it has no idea what-is-what unless you give it an absolute. Do you not zero your bathroom scale before you weigh your fat ***? Makes you feel better when you weigh 10 lbs "less." If you're not metering the atmosphere, then you're calibration will be incorrect.
I, unlike AFRman here, have no idea when my AFRs are correct unless my WB tells me. If I tell my WB that 14.7:1 AFR is actually 14.0:1 because there's residual gas floating around the pipes, then it'll always be incorrect. But how will I be the wiser?
Also, the proper procedure for the calibration is holding the button down for three seconds, then it starts to calibrate. IIRC, it calibrates for something like 5 seconds. That's kind of a long time to gamble that the ECU is cutting enough fuel long enough depending on the conditions. (Also have you ever turned off your car and continued to meter the exhaust? I betcha it doesn't read lean right away, nor after ten minutes)
Then after all that you're even supposed to power off the WB and turn it back on after 30 seconds to store the calibration into memory.
Why not get off your ***, unscrew the sensor and let the read the atmosphere, do the free-air calibration and screw it the **** back in. I tend not to try to gamble with things that need to be "accurate."
#22
Boost Pope
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What kind of display gauge are you using?
The problem you're having is either wiring (ground offset for example) or software settings in either the MS or the LC1. If you have the ability to generate a precise reference voltage, you can test the MS's calibration by applying exactly 2.5v to its input, which should cause a reading of appx 14.9:1.
Fortunately, the LC1 allows you to custom-tailor the calibration of the outputs, so you can correct for offsets. Just make sure that whatever you're using as a reference (ie: the display gauge) is actually correct before you go tweaking the outputs. This is the thing I like best about the XD-16 gauge- since it communicates digitally with the LC1, it's guaranteed to show you precisely what the LC1 is actually calculating, and cannot be affected by offsets or output miscalibration.
#23
It's a bad practice; really bad.
The sensor is supposed to be in "free-air" for the calibration. We are talking about an import device here that requires accuracy. The entire purpose of the free-air calibration is so the sensor knows what 20.2% oxygen content "feels" like. Remember, you're calibrating the sensor, it has no idea what-is-what unless you give it an absolute. Do you not zero your bathroom scale before you weigh your fat ***? Makes you feel better when you weigh 10 lbs "less." If you're not metering the atmosphere, then you're calibration will be incorrect.
Also, the proper procedure for the calibration is holding the button down for three seconds, then it starts to calibrate. IIRC, it calibrates for something like 5 seconds. That's kind of a long time to gamble that the ECU is cutting enough fuel long enough depending on the conditions. (Also have you ever turned off your car and continued to meter the exhaust? I betcha it doesn't read lean right away, nor after ten minutes)
Then after all that you're even supposed to power off the WB and turn it back on after 30 seconds to store the calibration into memory.
The sensor is supposed to be in "free-air" for the calibration. We are talking about an import device here that requires accuracy. The entire purpose of the free-air calibration is so the sensor knows what 20.2% oxygen content "feels" like. Remember, you're calibrating the sensor, it has no idea what-is-what unless you give it an absolute. Do you not zero your bathroom scale before you weigh your fat ***? Makes you feel better when you weigh 10 lbs "less." If you're not metering the atmosphere, then you're calibration will be incorrect.
Also, the proper procedure for the calibration is holding the button down for three seconds, then it starts to calibrate. IIRC, it calibrates for something like 5 seconds. That's kind of a long time to gamble that the ECU is cutting enough fuel long enough depending on the conditions. (Also have you ever turned off your car and continued to meter the exhaust? I betcha it doesn't read lean right away, nor after ten minutes)
Then after all that you're even supposed to power off the WB and turn it back on after 30 seconds to store the calibration into memory.
Next, I wouldnt be recommending the **** unless I was certain it worked. If you dont believe me, go cold start your car and get a recording of your AFR gauge for the first 10 min. Then go for a drive and recalibrate exactly how I describe. Wait till tomorrow and restart the car again. The readings will be the same aside from whatever minor descrepency due to temperature changes.
Youre right on one thing, if you just shut off the engine there is exhaust gas lingering. But now go floor your engine and rev to 7k rpm stationary, and turn the key off. I bet you it will be clean.
I had mine running in my exhaust without power for 2 weeks, which you apparently are not supposed to do, guess what the **** still works. Explain what difference its supposed to make if its powered or unpowered, the damn thing is already floating around in something like 500+ F temps.
Bottom line, this thing is not that fragile.
Last edited by Saml01; 05-05-2009 at 03:36 PM.
#24
The one that came with the LC-1, "DB" model, blue if that makes a difference .
DB Gauges: Air Fuel Ratio Guage
The problem you're having is either wiring (ground offset for example) or software settings in either the MS or the LC1. If you have the ability to generate a precise reference voltage, you can test the MS's calibration by applying exactly 2.5v to its input, which should cause a reading of appx 14.9:1.
All of my grounds for LC-1 controller and gauge are on the same lug, at back of intake mani with the ECU grounds.
If it were <0.5 discrepancy I wouldn't care, at least not until I got into hustler territory or start WI.
>0.5 causes a little concern, although at least the MS is getting the leaner reading, and this is what goes on the datalogs. Although being nearly a full point too rich can be bad news as well.
I'm about to just recalibrate, and reset the linear settings on wideband controller. I've done it twice already...but still consistently see leaner values on MS dash gauge versus actual gauge. The gauge may just be that far off, or it may be the amount of time it takes the eyes to travel from one to the other, but it's pretty consistently off, and worth figuring out.
DB Gauges: Air Fuel Ratio Guage
The problem you're having is either wiring (ground offset for example) or software settings in either the MS or the LC1. If you have the ability to generate a precise reference voltage, you can test the MS's calibration by applying exactly 2.5v to its input, which should cause a reading of appx 14.9:1.
If it were <0.5 discrepancy I wouldn't care, at least not until I got into hustler territory or start WI.
>0.5 causes a little concern, although at least the MS is getting the leaner reading, and this is what goes on the datalogs. Although being nearly a full point too rich can be bad news as well.
I'm about to just recalibrate, and reset the linear settings on wideband controller. I've done it twice already...but still consistently see leaner values on MS dash gauge versus actual gauge. The gauge may just be that far off, or it may be the amount of time it takes the eyes to travel from one to the other, but it's pretty consistently off, and worth figuring out.
#26
Boost Pope
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This might explain it. Ideally, the wideband (and gauge) should be grounded as near as possible to the ECU. This means splicing into one of the MS's ground wires, not merely running a separate wire to the head. It seems counterintuitive, however the goal is not to give the LC-1 the "best" possible ground, but to make sure it sees the same ground as the LC-1.
#27
This might explain it. Ideally, the wideband (and gauge) should be grounded as near as possible to the ECU. This means splicing into one of the MS's ground wires, not merely running a separate wire to the head. It seems counterintuitive, however the goal is not to give the LC-1 the "best" possible ground, but to make sure it sees the same ground as the LC-1.
EDIT: MS and LC-1 grounds have seperate wires, but not grounded to seperate parts of the head. Those two lugs are on top of each other, with the same bolt attaching them to the head. I should really know how important grounds are from car stereo days, but for some reason they always get so little attention, and not just from me I've noticed.
I'm about to just cut every single ground wire, weld(er, solder) them ALL onto on big lug, and torque it down to 22ftlbs.
#28
Boost Pope
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Yeah, even if they're grounded to the same bolt. It's the voltage drop across the MS's ground lines (due to sinking high-current stuff like injectors) that's the concern. IOW- the potential at the MS side of the ground wire may be slightly higher than at the head side of that same wire.
#29
Ok, thanks for that explanation...that's enough to explain the small difference, despite what seems to be a commonly used setup.
So if I splice into the MS ground wire -at the head- or solder them all together I should get the same potential for all the ground wires?
I barely made it through my electrical engr. classes, but I don't see any reason to splice further upstream.
So if I splice into the MS ground wire -at the head- or solder them all together I should get the same potential for all the ground wires?
I barely made it through my electrical engr. classes, but I don't see any reason to splice further upstream.
#30
Youre getting wrong readings not because of bad grounds, you have your software set up incorrectly.
I have a shared ground wire running from the throttle body to behind the exhaust manifold. From those points they split off to the MS/LC1, to my DB Gauge and other gauges, and IAT sensor. Everything works.
I have a shared ground wire running from the throttle body to behind the exhaust manifold. From those points they split off to the MS/LC1, to my DB Gauge and other gauges, and IAT sensor. Everything works.
#37
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Well, I never did solve the discrepancy between the Glowshit gauge and Megatune.
I just unplugged the gauge and it lives on top of my toll box.
On a brighter note, my friend helped by coming up with a good AFR table. We drove around the twisties while logging and came up with a good tune. The car runs really good now.
Now I need money for a turbo
I just unplugged the gauge and it lives on top of my toll box.
On a brighter note, my friend helped by coming up with a good AFR table. We drove around the twisties while logging and came up with a good tune. The car runs really good now.
Now I need money for a turbo
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