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Old 01-03-2012, 01:41 PM   #1
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Default Is this a noisy or normal signal?

I'm a bit worried. My gauge will only go to 21.5 full lean instead of 21.9, and last time this happened my o2 signal was ridiculous. This is not as bad, but the frequency is way faster.

Am I just being paranoid?

I'm assuming it may just be a gauge problem, this log shows 21.9
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Old 01-03-2012, 01:50 PM   #2
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Looks very noisy imo. Check/add grounds to everything until you fix it.
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Old 01-03-2012, 04:33 PM   #3
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One good way to check for noise is to add max delay to the sensor and then see what the ouput looks like.
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Old 01-03-2012, 08:21 PM   #4
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looks like noise to me, do you have it grounded to the same place as your megasquirt?
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Old 01-04-2012, 01:29 AM   #5
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Its grounded to the same place as the MS. I havn't touched anything. This always seems to happen after 5-6 months. The signal goes noisy without me touching anything at all.
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Old 01-04-2012, 02:22 AM   #6
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Solution: buy a UEGO instead of lc-1, win. Thats what I had to do to keep my sanity.
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Old 01-04-2012, 04:17 AM   #7
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Originally Posted by wittyworks View Post
Solution: buy a UEGO instead of lc-1, win. Thats what I had to do to keep my sanity.
I constantly throw this idea around. The lack of reliability of this thing is driving me up a wall.
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Old 01-04-2012, 08:57 AM   #8
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I constantly throw this idea around. The lack of reliability of this thing is driving me up a wall.
Tell us exactly how it's wired-up. Specifically, where is the gnd for the computer, the gnd for the WB heater, gnd for the wideband sensor, and anything else notable.

I've installed/fixed 6 LC-1s and never had a problem.
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Old 01-04-2012, 08:58 AM   #9
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Quote:
Originally Posted by wittyworks View Post
Solution: buy a UEGO instead of lc-1, win. Thats what I had to do to keep my sanity.
It's funny you mention this. I started with a UEGO and switched to an LC1 after a lot of frustration with offset of the analog output.

Wideband systems are finnicky, and they're just barely mainstream tech at this point. Folks have had problems and success stories with pretty much every unit out there.
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Old 01-05-2012, 01:46 PM   #10
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Quote:
Originally Posted by hustler View Post
Tell us exactly how it's wired-up. Specifically, where is the gnd for the computer, the gnd for the WB heater, gnd for the wideband sensor, and anything else notable.

I've installed/fixed 6 LC-1s and never had a problem.
All the grounds are spliced into one ground. That ground is then spliced into the ground at the MS harness. black/green wire I believe.

power comes from the radio.
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Old 01-05-2012, 01:49 PM   #11
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Quote:
Originally Posted by MartinezA92 View Post
All the grounds are spliced into one ground. That ground is then spliced into the ground at the MS harness. black/green wire I believe.

power comes from the radio.
its generally not a good idea to share power/analog and signal/digital grounds.

btw, I have an MTX-L and have zero ground problems (my ground is at the dash).

plus splitting the grounds up is generally better anyways, although not likely to matter in many cases.
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Old 01-05-2012, 02:48 PM   #12
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I would add some more grounds first, but if that fails find a better power source that isn't shared.
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Old 01-05-2012, 03:59 PM   #13
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The LC-1 has a built-in smoothing function, BTW. You may need to play with that a bit.
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Old 01-06-2012, 12:56 AM   #14
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The LC-1 has a built-in smoothing function, BTW. You may need to play with that a bit.

whut

Details? I've never even heard of this.
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Old 01-06-2012, 02:08 AM   #15
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Yeah seperate piwer and signak ground
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Old 01-06-2012, 02:21 AM   #16
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Out of curiosity where do you guys get your power from, and where do you put your grounds? Not in much of a mood to experiment, I want to make this work the first time (or in this case like the 5th time).
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Old 01-06-2012, 10:12 AM   #17
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Any ole key-switched white wire with red stripe
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Old 01-06-2012, 10:33 AM   #18
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Quote:
Originally Posted by MartinezA92 View Post
Out of curiosity where do you guys get your power from, and where do you put your grounds? Not in much of a mood to experiment, I want to make this work the first time (or in this case like the 5th time).
Spliced power from the radio ignition wire (I think it was blue and black for me, blue and red was constant 12v).

I ground it on the support brace for the center dash. I pretty much crimpped the dimming wire with the ground and bolted it to the brace.

I think you have two separate grounds right? If they are coming out of the sensor, you should look for something in that area, but away from the exhaust. if your grounds are coming out of the gauge (like mine), I would find a decent area under the dash. glove box area has a few bolts you can use too.

just make sure you clean any paint off from under the bolt/crimp.
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Old 01-06-2012, 11:14 AM   #19
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Quote:
Originally Posted by MartinezA92 View Post
Out of curiosity where do you guys get your power from, and where do you put your grounds? Not in much of a mood to experiment, I want to make this work the first time (or in this case like the 5th time).
Splice/plug into power window connector (near shifter), plenty of current there... and if you don't have power windows you can actually just plug into the connector with crimp connectors. Use the ground there for power ground. I've done a couple cars this way with LC1 and 14 point 7 WB. Both cars are winning to this day. (make sure the signal ground is run to the sensor ground close to the ECU)
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Old 01-06-2012, 01:37 PM   #20
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Quote:
Originally Posted by MartinezA92 View Post
whut

Details? I've never even heard of this.
Look at section 6.5.1 ("Advanced Output Programming") of the LC-1 Manual on pages 14 and 15. You can setup the analog output to either be instantaneous or have up to 1/3 second of smoothing. This might help your noise.
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