MS2/Extra need help with odd CLT temp drop above 176c

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OctaneDBS
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MS2/Extra need help with odd CLT temp drop above 176c

Post by OctaneDBS »

Hi All

I am new here and seek help for an odd problem i have with my new install in a 76 vert stock fi superbeetle,
I have tried 3 different CLT sensors that have a range between -40 and 250 deg celcius but for some reason when the head temp on my aircooled engine reached above 176 degrees celcius it drops to 80 degrees (on the dash and in the logs), i have a gut feeling it has to do with a fail safe temperature and maybe the wrong bias resistor (2490 stock) but cant put my finger on it beside's the drop the temp is accurate (confirmed with ir thermal gun).

Has anybode else experienced this or any clue to what it might be ?

Log is attached

Thanks
Regards

OctaneDBS
Last edited by OctaneDBS on Mon Sep 19, 2016 5:28 am, edited 1 time in total.
OctaneDBS
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Re: MS2/Extra need help with odd CLT temp drop above 176c

Post by OctaneDBS »

Can anyone with some knowledge of the source code please have a look ?
i attached the current tune incase it holds some clues

thanks

Barry
Matt Cramer
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Re: MS2/Extra need help with odd CLT temp drop above 176c

Post by Matt Cramer »

What is the calibration curve for the sensor you are using?
Matt Cramer -1966 Dodge Dart slant six running on MS3X
OctaneDBS
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Re: MS2/Extra need help with odd CLT temp drop above 176c

Post by OctaneDBS »

Hi Matt the calibration curve is

Bias resistor is 2490

100 - 3267
24,5 - 48500
-14 - 349400

the sensor is a Koso BF100000 that runs up to 250 deg celcius (drop in fit and the resistance and temp are verified they do match up)

i noticed this morning that the drop is from 176,6 deg Celsius (350 F) down to 82,2 deg Celsius (180 F) coincides with the temp gauge redlining is there any way to change the scale ?(i already have the Air-Cooled extended clt range enabled)
So it looks like the temp reads correctly but the limitation is in the software somewhere

Barry
hybrid
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Re: MS2/Extra need help with odd CLT temp drop above 176c

Post by hybrid »

Gauge limits can be changed:
http://www.tunerstudio.com/index.php/ma ... uge-limits


It would seem strange if something in tunerstudio was affecting the behaviour of the ECU itself though.
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Re: MS2/Extra need help with odd CLT temp drop above 176c

Post by jsmcortina »

This is TunerStudio's doing. I used your calibration values and the highest temperature value in the calibration data it generates is 349degF = 176degC.

The firmware is just reporting the data that TunerStudio gave it. I've uploaded the calibration results.

Moving topic to TunerStudio sub-forum.

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OctaneDBS
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Re: MS2/Extra need help with odd CLT temp drop above 176c

Post by OctaneDBS »

Thanks for the link !
That did allow me to change the gauge, but like you said i am not sure if the changes the behaviour the the ms itself (got to go test it)

Barry
OctaneDBS
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Re: MS2/Extra need help with odd CLT temp drop above 176c

Post by OctaneDBS »

jsmcortina wrote:This is TunerStudio's doing. I used your calibration values and the highest temperature value in the calibration data it generates is 349degF = 176degC.

The firmware is just reporting the data that TunerStudio gave it. I've uploaded the calibration results.

Moving topic to TunerStudio sub-forum.

James

Indeed ! i see it in my gentherm.log as well is there any way to generate and upload the file in another way by using a custom inc file ?
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Re: MS2/Extra need help with odd CLT temp drop above 176c

Post by LT401Vette »

There are ini defined limits with a default value if you go outside those limits. The assumption is if you go out of the limits the sensor is bad, so go to a default.
in the therm generator, the ini section has a default section in the TS installer that is used unless it is over-ridden in another ini. The TS default is defined in
[TunerStudioInstallFolder]/inc/ms2ReferenceTables.ini

The limits and defaults are:

Code: Select all

#if EXPANDED_CLT_TEMP 
                 id,   min, max, default
	tableLimits = 000, -40, 400, 350
#else
	tableLimits = 000, -40, 350, 180
#endif

Thus if you have EXPANDED_CLT_TEMP set, then:
min = -40
max = 400°F
default = 350°F

If EXPANDED_CLT_TEMP is not set:
min = -40
max = 350°F
default = 180°F


I think the problem may be that EXPANDED_CLT_TEMP is no longer supported in the newer firmwares, so we may need to come up with something new there.

But, your quick answer is, yest dropping in a custom.ini with an updated [ReferenceTables] will let you use the full range.

Drop the attached custom.ini into the folder:

[YourTunerStudioProject]/projectCfg/

TS will use it instead. The limits for the CLT sensor are:
min = -40
max = 475°F
default = 350°F
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OctaneDBS
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Re: MS2/Extra need help with odd CLT temp drop above 176c

Post by OctaneDBS »

That worked perfectly ! :yeah!:

Thanks for the help, really appriciated!!

Barry
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