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Old 06-23-2010, 12:18 AM   #1
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Default LC1 readings- lolwut?

So one night I plan to go on a mountain run with a shitload of my friends. My LC1 decides to start reading ridiculously lean. I recalibrate, same thing. I freak out thinking I'm running way lean. Idling/cruise around 18-19 and WOT is 14-15. I plug in my stock ECU and I get the same readings. Check fuel pressure: everything checks out fine. Decide that its the LC1 being stupid if the stock ECU still gives me wayyy lean readings. Over the past few days its gotten worse, my gauge now reads 22 at idle sometimes (I didn't even know it went past 21.9), and when I start up the car and the LC1 heats up, it fluctuates between 7.4 and 7.6 and the number inconsistently flashes.

wat?

MS is getting the same numbers, so I know its not a gauge problem. I'm pretty damn convinced I'm not actually running lean, there isn't any drivability problems to speak of, no lack of power that is noticable, nothing has changed.
Anyone have any thoughts/had this happen to them?
I don't even pay attention to the gauge anymore, but I want this **** done right.
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Old 06-23-2010, 09:36 AM   #2
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Does/is the LC1 using the same sensor as the MS? Power source? Ground?
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Old 06-23-2010, 09:50 AM   #3
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Most likely a wiring issue. Make sure you power and ground wires are all solid. Did you ground the LC1's black wire?
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Old 06-23-2010, 12:44 PM   #4
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is the LED flashing?
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Old 06-23-2010, 12:46 PM   #5
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When are you going to fix your exhaust leak?
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Old 06-23-2010, 01:31 PM   #6
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LED flashes like normal for warm up, stays lit when driving.
Power is coming from radio, grounded at same location as MS.
I don't hear any exhaust leaks, I'd think it'd be pretty obvious. Of course knowing me, I'm probably wrong.

I'll triple check my wiring tonight.
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Old 06-24-2010, 08:08 PM   #7
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My LC-1 does things like that too. It will work fine one day and then it will **** the bed. No amount of recalibrations do anything. Give it a few days, threaten to pull it out if it doesn't recalibrate and guess what, it works fine again. Piece of **** is my take on it. What other brands of WB work well with the MS??
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Old 06-24-2010, 08:28 PM   #8
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Uego is another popular one I think.

The LC1 seems to work better on cold starts...within seconds of driving it pegs lean again though.
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Old 06-25-2010, 12:18 AM   #9
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Wiring is in front of me as I type this. Nothing seems odd. Exactly how I left it.
I have the key turned to ACC and the LC1 is doing something its never done before when the car is off....its jumping from 11 to 21. What a pile. I've tried playing with the wires seeing if I get any obvious changes, and nothing. Started it up and it read 14...then slowly went up to 18.

EDIT: I recalibrated heater and sensor. Everything looked good for about 30 seconds, now its still reading too lean, but not as much. Now at WOT it actually reads what it should be, or at least pretty damn close.
Im about to break this thing.

Maybe braineack is right.

Last edited by MartinezA92; 06-27-2010 at 02:45 AM.
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Old 06-29-2010, 09:03 PM   #10
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Pull the sensor and look at it, is it coated in ****? Wait till it cools, disconnect it and try spraying it with carb cleaner and wiping it dry.

Does your mx burn oil?
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Old 06-29-2010, 10:31 PM   #11
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Quote:
Originally Posted by flounder View Post
Pull the sensor and look at it, is it coated in ****? Wait till it cools, disconnect it and try spraying it with carb cleaner and wiping it dry.

Does your mx burn oil?

Will try this next. Gonna reweld around the bung, I think that if there IS an exhaust leak, it may be from there.
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Old 07-01-2010, 11:32 AM   #12
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I had the same problem.
Was running lc1 with a link,inconsistant readings ,usually lean, even after replacing sensor.
I was also running a separate narrow band gauge which did not correspond to the wideband output.

Now it is near perfect.
How did I fix it?
I reluctantly replaced the lc1 with an AEM wideband with gauge
Tuning has never been easier
I have to say it was the best $200 I've spent on the turbo system
I still run a narrowband gauge as a redundant comparison

Anyone want to buy my "working" lc1?
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Old 07-01-2010, 09:39 PM   #13
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Second to last resort is replace the sensor itself. If that still doesn't fix it I'm throwing this piece of **** in the garbage where it belongs and buying a Uego.

Gotta check the weld at the bung too for a leak. So tired of this pile.
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Old 08-04-2010, 06:53 PM   #14
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Just because I don't like leaving threads without closure...New sensor fixed my problem.
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Old 08-05-2010, 10:39 AM   #15
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Old 11-17-2013, 08:40 PM   #16
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Wow!!! I'm having the same problem with my LC-1

I originally blamed it on one MSQ I loaded.

I've done the sensor cleaning, fre air calibration etc.

All of my important grounds are together and I've never had an issue with the gage

What are the chances a new sensor will fix things ?

Sensor is a big cost compared to the gage
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Old 11-17-2013, 08:46 PM   #17
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Well I'd say the chances are pretty good since it fixed OPs problem. But you may as well check for any exhaust leaks since that's free.
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Old 11-17-2013, 08:59 PM   #18
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Quote:
Originally Posted by FRT_Fun View Post
Well I'd say the chances are pretty good since it fixed OPs problem. But you may as well check for any exhaust leaks since that's free.
Thanks that's a good idea .
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Old 11-18-2013, 02:53 PM   #19
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Yeah it's probably the sensor. They only last a couple years in daily driving conditions, and if you're too rich or lean that will limit the life as well.
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Old 11-18-2013, 03:33 PM   #20
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What is it about cars that makes them NOT act up when they know they are under scrutiny.

I got a brand new sensor from O Rileys sitting in my front seat

The AF readings have not acted up all day
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