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Old 02-06-2011, 05:50 PM   #1
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Default Car leans out, loses power and dies

This seems to happen when the car has warmed up a bit, and I have no idea why. My tune is super rich right now, because I haven't been able to tune it away.

The only things I can think of would be moving the ground from the IM to the block for the ECU and WB, and that the sensor would be covered in soot. The latter doesn't make any sense as I'm not even in tuning when this happens.

Going to be switching grounds today, for starters. Anyone have a tip for how to clean an O2 sensor?

Any ideas on what this could be? It gets better when I restart, until it acts up again.
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Old 02-06-2011, 06:23 PM   #2
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Datalogs and msq?
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Old 02-06-2011, 06:45 PM   #3
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Fuel pump?
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Old 02-06-2011, 06:55 PM   #4
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Fuel pump should be just fine, it's been fine, and the car is ok except for... when it's not. Runs rich until then, actually since I'm still on basemaps.
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Old 02-06-2011, 10:01 PM   #5
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Fuel pressure spikes when it goes lean - runs perfectly untill this happens, then fuel pressure spikes in time with it going lean.
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Old 02-06-2011, 10:41 PM   #6
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Please have a look at my log...

Check out what my spark does, then my fuel pressure, then my O2... so weird.
Attached Files
File Type: msl 2011-02-06_17.48.53.msl (1.66 MB, 74 views)
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Old 02-06-2011, 11:11 PM   #7
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The car dies at about 800, 878, 1272...
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Old 02-07-2011, 08:12 AM   #8
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first your running on a basemap.


second your running barometric corrections. thrid, even if you HAD a second MAP sensor, the spread you allow baro to correct is WAY too high.
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Old 02-07-2011, 09:27 AM   #9
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Quote:
Originally Posted by Nagase View Post
Please have a look at my log...

Check out what my spark does, then my fuel pressure, then my O2... so weird.
Your spark angle makes sense as it follows the MAP/RPM table combo. Your fuel pressure...you don't have a fuel pressure sensor somewhere on your car, now do you? And on inspection, your "fuel pressure" is following your O2 signal verbatim...so its not the fuel pressure you are seeing.

Btw if you had a TPS, it would have been much easier to diagnose things.
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Old 02-07-2011, 09:31 AM   #10
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the problem is the barometric corrections. turn them off and it wont happen again.
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Old 02-07-2011, 11:57 AM   #11
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I feel like I've seen this discussion recently - the previous OP had an injector stuck open, so the car was showing way rich until he got on the freeway and had to use a bit more throttle position, which quickly led to blowout and showed the AFRs as being too lean....


....or it could be what brain said, i don't know how to read a log yet
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Old 02-07-2011, 11:57 AM   #12
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oh it's what i said.
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