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Emerald datalogger trace


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Hmmm, possibly flex/movement/vibration over the years has introduced some fatigue to it? Nerdy answer is - get a 'scope on it and I could tell you :) but, yeah, redo the log trace as suggested and I suspect that will soon tell you. Also just watching the "live adjustments" screen while it's running, and while you're revving it/etc - would be easy to spot loss of crank signal as it would freak out with RPM reading. Try the sensor now you've ordered one but don't rule out the cable is all I mean, just in case it doesn't fix the issue ;)

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So, Emerald replied and sent me a new map file with extra ign corrections at 20 degC (same as Dan suggested) and blimey, that worked amazingly - car started on first turn of the key 😀

Attached is datalogger trace with more sensible parameters recorded - and I cannot see anything wrong with the engine speed (purple line) although I only went on a short drive and there was only a slight hint of misfire.

newMap.lg1 newMap.lg2

Edited by nelmo
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So, got a new crank sensor and went out for a longer drive with the datalogger on (quite fascinating this thing 😀) and I wonder if my problem is the TPS?

In the trace below, felt like the car was mis-firing - the yellow line is the throttle position; should it be jumping about that much (the middle section of that screenshot, between 6 and 18%) when I was keeping a fairly constant pressure on the pedal (slightly dropping off but nothing as dramatic as that trace suggests). Purple is revs, green is InjPW, white is InjDuration...


Full trace attached - quite a lot of this erratic throttle position trace in there.

Also had a weird blip at 20:49:50 where the engine almost stalled on a very small throttle input?

postNewCrank.lg1 postNewCrank.lg2

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I suspect they log the raw values, would make sense in terms of diagnosing issues like this, but you're right there's various acceleration values that would dampen the calculated injector timing and so forth so I doubt it's too much of an issue.

But some of those readings do look a bit noisier than other logs I've got from mine and other cars. Is your TPS sensor cabling shielded like your crank sensor? outer shield, earthed at ECU end only?

That blip - it properly leaned out then didn't it! In fact there's a lot of points where it goes very lean - steady throttle seems fine (there's not many points on there though where it's like that) but looks like the idle fueling needs some fettling. Might be idle stabilisation function, or something more physical.


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