Also where does the OBC get these readings from and how accurate are they.
Thanks (in advance)
On board comedian question.
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leeparkes
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On the 13 button OBC press consumtion and you can switch between MPG or M/G via the little dot in the corner, but they give different readings. Why? Which one should it be on for UK?
Also where does the OBC get these readings from and how accurate are they.
Thanks (in advance)
Also where does the OBC get these readings from and how accurate are they.
Thanks (in advance)
Cypriotgeeza wrote:I done both my mates in my old 318is
felt so proud,even tried it with a E30 325i and got put in my place..
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Brianmoooore
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OBC calculates how much fuel is being used by measuring the width of and counting the injector pulses. Accuracy depends on how close to spec. your injectors are.leeparkes wrote: Also where does the OBC get these readings from and how accurate are they.
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leeparkes
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Ah, i see, injectors were cleaned recently by injectortune but the engine is an M30.
Is there a way to calibrate the OBC to match?
Is there a way to calibrate the OBC to match?
Cypriotgeeza wrote:I done both my mates in my old 318is
felt so proud,even tried it with a E30 325i and got put in my place..
Difference between US and imperial gallons:
There are 8 pints to the gallon.
Imperial pint is 20 fluid ounces
US pint is 16 fluid ounces
This is where the 20% difference that lowey mentioned comes from.
There are 8 pints to the gallon.
Imperial pint is 20 fluid ounces
US pint is 16 fluid ounces
This is where the 20% difference that lowey mentioned comes from.
Schadenfreude - the German's haven't got a word for that.
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HairyScreech
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i have wondered if its possible to re calibrate the obc as well, im not 100% sure it can be done but it would be nice if possible for once i have built the 2.8.
2.8 development thread http://www.e30zone.net/modules.php?name ... c&t=170822
m3.3.1 m20 thread - now running, chip needed - any volunteers?
http://www.e30zone.net/modules.php?name ... =viewtopic&
m3.3.1 m20 thread - now running, chip needed - any volunteers?
http://www.e30zone.net/modules.php?name ... =viewtopic&
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Rav335uk
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Surely, if this is reading pulse from the injectors, it should work correctly with any engine in then??
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CR24v??? Where's it all gone?? LOL
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Brianmoooore
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No, because these injectors are delivering more fuel that the OBC expects, so it will think the car is using less fuel than it actually is.Rav335uk wrote:Surely, if this is reading pulse from the injectors, it should work correctly with any engine in then??
I don't know of any easy way of recalibrating, but I've never looked into it.
There may be an internal calibration pot., or you could add some electronics in the fuel rate signal wire between the ECU and the instrument cluster to reduce the number or width of the pulses pro ratia, or it may be possible to target whatever is used inside the OBC to switch between litres, imperial gallons and US gallons.