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LC-1 Problems? What is yours doing?

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Old 05-13-2007, 05:58 PM
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Default LC-1 Problems? What is yours doing?

I notice the last time I dynoed, there was a significant difference (Like 2 points) between the dyno's WBO and my LC-1.

Now it seems that it may be getting worse. My cruising AFR used to be spot on around 14-14.5. Now they report as 16-16.5. Only problem is I still have soot on my tailpipe.

I know in other threads, others have had problems. What is yours doing when you call it "dead"?
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Old 05-13-2007, 06:00 PM
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Do a free air calibration.

Ben

<edit> Oh, don't expect your $50 bosch sensor to be as accurate as the dyno's $1000 sensor.
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Originally Posted by concealer404
Buy an MSPNP Pro, you'll feel better.
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Old 05-13-2007, 07:46 PM
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Originally Posted by Ben
Do a free air calibration.

Ben

<edit> Oh, don't expect your $50 bosch sensor to be as accurate as the dyno's $1000 sensor.
Just ground the black wire on the LC-1 for like 10 seconds?

Did that, have not driven enough to see if that fixed it.
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Old 05-13-2007, 09:41 PM
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No, unplug the sensor from the controller, turn the ign on, count to 10, turn ign off, plug sensor back in, turn ign on. This will cause a full calibration. It should take like 2 minutes. If you don't have an xd gauge you can hook up your laptop to the lc to watch calibration progress.

The sensor needs to be in free air during calibration, or at least wait 12+ hours after running the car if the sensor has to stay in the pipe.

When is your AFR reporting lean? Idle, cruise, both? Lean at idle/light load but stoich under cruise is a vac leak and not a problem with the LC.


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Originally Posted by concealer404
Buy an MSPNP Pro, you'll feel better.
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Old 05-13-2007, 10:46 PM
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My LC1 reads from 0-50 on my guage and tries to hang at 14.8 on my MS no matter what. I should have a new controller soon though.
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Old 05-14-2007, 02:20 AM
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To be fair, I'm pretty sure I got one of the bad ones off Ebay.

First, I had batt voltage on analog 1 so I cut open the LC-1 case and fixed the short. Now, I've noticed the AFR gauge in MegaTune occasionally showing about 1.5 richer than it should be. When I restart it's fine again. I'm N/A and I have the stock ECU in parallel so I'm using it for a baseline 14.7 at idle.

I wasn't sure if it was MS or the LC-1. I'm thinking about ordering the JAW for $40 and using it for comparison.

BTW, on the quick calibration, when you ground out the black wire what's supposed to happen? I see the red light blink for 1/10 of a second then it comes back on. I was expecting something more like the 1st time cal where it takes a minute or two to complete.
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Old 05-14-2007, 07:18 AM
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Originally Posted by Ben
No, unplug the sensor from the controller, turn the ign on, count to 10, turn ign off, plug sensor back in, turn ign on. This will cause a full calibration. It should take like 2 minutes. If you don't have an xd gauge you can hook up your laptop to the lc to watch calibration progress.

The sensor needs to be in free air during calibration, or at least wait 12+ hours after running the car if the sensor has to stay in the pipe.

When is your AFR reporting lean? Idle, cruise, both? Lean at idle/light load but stoich under cruise is a vac leak and not a problem with the LC.


Ben
Its super lean cruising with or without an above average load (towing my tire trailer makes no difference).

WOT- Rock solid 13.8-13.9
Idle- Lean like cruise

I'll try the FULL calibration tonight. Thanks!
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Old 05-14-2007, 09:05 AM
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Originally Posted by Ben
The sensor needs to be in free air during calibration, or at least wait 12+ hours after running the car if the sensor has to stay in the pipe.
And IMO I'd just pull it out and leave it in the free air. After all this is what you're using to tune the AFR and I'd rather be sure about the calibration. Having it off on the rich side might be tolerable, but "what if" it's the other side?
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Old 05-14-2007, 09:15 AM
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If you are running a cat there can be (but not necessarily) a 0.5-1 difference between your pre-cat LC-1 and post-cat sniffer, but a 2 point difference sounds like a lot.
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