Author Topic: Funny datalog feature - possible misfire but need other people's thoughts...  (Read 4615 times)

Offline dnb

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Here's a short section from a recent datalog I analysed.  I was not driving the car or indeed anywhere near it, so I don't know what really happened.  I think the car misfired for some reason while pulling out of a junction, but I don't know why it would want to do such a thing.  I am told that when pulling away from the junction, there was no power, and suddenly when the throttle was released a bit there was a little bit too much...  The car does not often perform this way for me - maybe I have lead boots or something. ;)



The X axis is time in datalog units (seconds I think)
The left hand Y axis is RPM
The right hand Y axis is used for all other series.

Everything is named in the same way as in a MT datalog except MAD_spark, which is my new misfire detection algorithm.  (see the thread in the new features area.)

As you can see, whatever caused the problem triggered the misfire detector extremely well.  But was it really a misfire?  Lambda shows no sign of becoming excessively lean apart from at one data point which I don't really believe anyway.  Lambda spends most of the time sitting at 0.96 - rich, but OK for warmup.  Nothing seems amiss in the logs apart from the misfire detector.

I could really use some opinions on this! 

Thanks.