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Old 04-04-2016, 09:47 PM   #1
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Default Bad Autotune, replace 02?

Just wanted to get a sanity check from you guys. New MSPNP ecu from Brain just installed. Purrs like a kitten when it idles on the base tune Brain loaded and runs smoothly in all gear and under boost.

I tried letting it autotune today and the passenger watched it consistently hit 7.6 AFR (idles at 10.3) and there was an error message on the autotune screen saying "Sensor out of range". The tune got worse and worse as we drove and cleared up when I restarted the car back on base tune.

The reason I got the new ECU was to datalog and figure out my overheating issue. I am starting to think that the old ecu was also tuning the car too lean and that is why I was getting over heating and glowing manifolds.

So, having cleaned the WB02 sensor last year when I was trying to diagnose things, do you guys suggest I just get a new sensor? It idles rich for sure so could have very easily gotten fouled. A quick google search has people suggesting replacing over cleaning since cleaning doesn't always work.

Thanks for any advice!
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Old 04-04-2016, 09:51 PM   #2
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Have you tried to tune it leaner? Autotune is going to work better when you're at least relatively close to your target.
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Old 04-04-2016, 09:53 PM   #3
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No, I hadn't gotten that far. Just working off of an initial gut feeling that the sensor might be bad. If the sensor is reading 7.6 AFR under load, could that be normal?
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Old 04-04-2016, 10:12 PM   #4
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If the engine is not experiencing 7.6 AFR, then no, it's not normal. I doubt it would run well at that AFR, does it?
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Old 04-04-2016, 10:16 PM   #5
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it runs pretty smoothly on the base tune, just some hickups at light load/throttle. It just runs rough when it starts to autotune
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Old 04-05-2016, 12:22 AM   #6
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Your wideband isn't giving a valid signal. If you were really at 7.6 AFR, your engine would be flooded. At 10 AFR you should be belching black smoke.

Don't touch the tuning until you figure out whats up with the wideband.
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Old 04-05-2016, 01:01 AM   #7
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What wideband. If its an innovate then 7.6 is their full rich reading. It could be richer than 7.6 and you won't know.
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Old 04-05-2016, 09:44 AM   #8
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Quote:
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Your wideband isn't giving a valid signal. If you were really at 7.6 AFR, your engine would be flooded. At 10 AFR you should be belching black smoke.

Don't touch the tuning until you figure out whats up with the wideband.
Thanks! This is what I wanted to hear since I don't know much about tuning and what values mean what for the engine. I will order a new o2 sensor when i get home and verify which one I have in my car.
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Old 04-05-2016, 09:44 AM   #9
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It is an LC-1 but I saw they have two types (4.9 and 4.2) so I will have to check. Good to know that 7.6 is its bottom range stop.
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Old 04-05-2016, 09:45 AM   #10
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Just have an LC1 and no dash gauge?
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Old 04-05-2016, 09:49 AM   #11
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The Dash gauge in there now is a colored bar that fluctuates back and forth between lean and rich and has never filled me with confidence on its accuracy. No actual numbers to verify with.
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Old 04-05-2016, 09:52 AM   #12
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Buy a new wideband O2 sensor. Either an MXT-L or an AEM EUGO. Quick dicking around around an lc-1.
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Old 04-05-2016, 09:53 AM   #13
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yeah it's 7.35-23.4:1 range.

double check the AFR calibration is set to innovate default.
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Old 04-05-2016, 09:55 AM   #14
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Hmm, I'll check the calibration settings when I get home. Why no love for the LC-1 Shuiend?
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Old 04-05-2016, 10:06 AM   #15
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Quote:
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Hmm, I'll check the calibration settings when I get home. Why no love for the LC-1 Shuiend?
Because they are old and shitty. You can't tell what it is actually reading compared to what TS shows. Every other wideband I have tried has had a slight offset in TS compared to the gauge for the wideband. Usually it is a small offset but you can calibrate the MS to read correctly. With the LC-1 that is next to impossible to do due to not knowing what it is actually outputting. I used LC-1 way back in the day. Now I won't touch one.
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Old 04-05-2016, 10:24 AM   #16
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I'll look into those other two sensors then, thanks!
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Old 04-05-2016, 10:44 AM   #17
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They are both around $150 on Amazon prime. Much cheaper then a new motor. Both will use the newest Bosch wideband sensor.
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Old 04-05-2016, 01:56 PM   #18
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Have you done a free air calibration like Innovate reccomends you do every so often? My friend bought a car with an LC2 in it and it would read max lean aby time you weren't in boost and max rich any time you were. A calibration cleared it right up.
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Old 04-05-2016, 02:14 PM   #19
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I did back when I cleaned it last year and I might try it after checking calibration and giving it one last clean to avoid buying new. If all else fails then I might just swap it out for the MXT-L
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Old 04-05-2016, 02:20 PM   #20
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The manual says to calibrate it when a new sensor is installed and again 3 months after that. Then, for a turbo car, every 6 months or 10k miles whichever comes first.
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