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downshift over-rev


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Hi folks

I would like to know if there's a way with an OBD2  fault code reader to know if there has been an over-rev, like one month (and more than 1000km) ago I downshifted from 3rd to 2nd instead of 4th by mistake in my 410 Sport, as soon as I felt the car's reaction and saw the red lights in the dash I pressed the clutch pedal (but not sure if i actually went beyond 7K revs) , there was no weird sound, no engine light and the engine has been running 100% smoothly since then, that is why I'm not even sure if the engine actually over-revved , would there be any fault code / log I can read with an OBD 2 connector if the engine actually over-revved (I need to do this for my mental health hahahaha)

 

Thank you

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Not with a normal code reader, especially if you have no warning lights. Lotus Techcentre can interrogate the ECU and give a report on engine speed history but I believe if there was an issue you'd know about it by now.

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Thank you @Arun_D, I will go to a Lotus dealer at some point for an ECU dump (the closest is 400km from where I live) , the car has been running smoothly for more than one month and 1K km since then, I don't even actually know if the engine was over-revved 

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It is logged in the ECU and you can extract the info via TechCentre.  It is "highest revs" for "x milliseconds".

 

However, there is some pretty funky stuff in there, which leads me to believe not all is 100% accurate.  (I have read somewhere that an "oil low event" gets triggered when simply draining and replacing the oil - not sure this is true at all; but there are some very strange examples of ECU readouts also on this forum, suggest a search).

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5 hours ago, Kristof Thys said:

It is logged in the ECU and you can extract the info via TechCentre.  It is "highest revs" for "x milliseconds".

 

However, there is some pretty funky stuff in there, which leads me to believe not all is 100% accurate.  (I have read somewhere that an "oil low event" gets triggered when simply draining and replacing the oil - not sure this is true at all; but there are some very strange examples of ECU readouts also on this forum, suggest a search).

I wish I could do that myself by apparently TechCentre software is almost impossible to get without being an official dealer 

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It's all available with a regular ODB2 plug, but no apps expose it directly as Mode22 (Enhanced Data) is manufacturer specific to Lotus.

But if you're handy enough with sending serial commands to your ODB plug, the mode 22 PIDs go from 0x200 to 0x3FF.

Last five recorded 'notable events' have their max engine speed at 0x31E, 0x31F, 0x321, 0x322, 0x323.

So issue the command to the ELM327 for the first stored RPM :

Quote

Command: 22 03 1E

You'll probably get a response like : 

Quote

7E8 07 62 03 1E 00 00 19 F0

Last four bytes are the 32bit representation of the RPMs, eg. 6640.

 

Edited by trcm
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All gleaned from the superbly smart 'cybernet'.

He for a long time maintained a wiki with all these in-depth reverse engineerings of the T4 and T6 ECUs, but he has sadly disappeared from these Lotus forums of late. 🙁

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