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Old 06-06-2011, 01:47 PM   #1
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Default LC1 errors at high RPM's

I just ran a track day at CMP and noticed the LC1 status light starting to flash when I stayed at rpms close to the 7400 redline before decellarating for a corner. The light would then keep flashing until I cut that car off and started it again. The logs show the AFR data dropping off as well. If I shift below 7000 it runs fine with no issues. Once I got off track and drove home I hit the rev limiter in second just to see if it would do it again and it didn't.

I had the problem on the street before when revving above 6000rpm, but that was fixed when I cleaned up all my wiring with soldered connections and removed all the crimp connectors. The LC1 is grounded per the instructions and I ran a 2 ga grounding wire from the battery to the LC1, Megasquirt and the started/engine.
Can the wideband sensor overheat? It sounds real stupid to me that something made to go in the exhaust can overheat but I had to ask.

Could'nt find anything in my searches either.
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Old 06-06-2011, 01:54 PM   #2
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Which code is it throwing? What firmware version are you on?
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Old 06-06-2011, 01:59 PM   #3
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I will have to look for the firmware, don't know off the top of my head. I didn't pay attention on the track to see what the code was (a little busy at that time) and forgot to look when I pulled in the pits. I will see if I can make it do it again on the street and then pay attention.
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Old 06-08-2011, 12:14 AM   #4
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Yes, the sensor can overheat. I've overheated my LC-1 with my stock 1.8, but only on the track. Datalogs showed 10:1 (0 volts from the sensor) but for reasons unknown to me the DB gauge would freeze on a much different value, like 15.0 or 15.1, something like that. Being naturally aspirated and with a known-solid tune I just kept driving it (made sure to turn off EGO control). It would cool off enough between sessions to read fine the next time the car was started.

Get one of those heat sinks made of copper sheet that you can mount between the sensor and the exhaust pipe. The dimensions are in the LC-1 manual if you want to make your own, and someone was selling them last year for <$20.
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Old 06-08-2011, 02:07 AM   #5
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Quote:
Originally Posted by ScottFW View Post
Being naturally aspirated and with a known-solid tune I just kept driving it (made sure to turn off EGO control).
What does the MS do if your LC-1 freaks out? I would think it just goes to its maximum authority that you allowed it to have...

Anyway, assuming its an overheating code, downgrade to firmware 1.0 (I did that a few months ago, never looked back), and if that doesn't work...heatsink.
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Old 06-10-2011, 09:05 PM   #6
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Looking at the codes it was eirther a 7 or 8 flash code so it could very likely have been related to heat. I will see if I can get a heatshield made. I was not running EGO correction while on track so it didnt mess anything up, I just did not have AFR's on the log for the whole run.
What does downgrading to previous firmware do for you?
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Old 06-11-2011, 01:58 PM   #7
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Upgrade the firmware to the 1.2 beta, it fixed a similar issue for me.
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Old 06-11-2011, 02:36 PM   #8
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A simple heatsink or moving the sensor further back should fix your problem. Innovate has a fancy billet heatsink you can buy if you want to be super baller, but a quick heatsink made from some scrap sheet aluminum or copper will work great. It's basically just a sheet with a hole drilled in it for the sensor tip to go through, and it sandwiches between the exhaust bung and sensor in the pipe. Takes longer to remove the sensor from the bung than it does to make the heatsink.
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Old 06-12-2011, 11:01 AM   #9
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I have some 16ga Aluminum laying around. I will try the heatsink and look into the firmware change as well. Thanks
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Old 07-17-2011, 06:08 PM   #10
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After doing some more reading I found out that my problem was more the overcooling that whould happen to the sensor as I let off the gas after a long hard run. The sensor heater cannot respond fast enough and causes the #8 failure. Seems that 90% of people get away with a firmware upgrade. I upgraded to the Rev 1.2 Beta firmware and it has been running great with no problems or flashing lights. The new revision has better heater control which eliminates the overcooling problem by responding faster and maintaining sensor temp.
If you are looking for the firmware do a sea rch on the innovative forums, it is attached to a post somewhere. They should release the final version soon.
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