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Pcmlogger and Flex Fuel
Posted: Thu May 27, 2021 1:58 am
by joukoy
What parameters I need for pcmlogger 15 to confirm Flex Fuel sensor operation?
I have added to "Parameters.Standard.xml":
Code: Select all
<Parameter
id="0052"
name="Ethanol 52"
description=""
byteCount="01"
bitMapped="False">
<Conversion units="%" expression="x/2.5" format="0.00" />
</Parameter>
<Parameter
id="12F3"
name="Ethanol 12F3"
description=""
byteCount="01"
bitMapped="False">
<Conversion units="%" expression="x/2.5" format="0.00" />
</Parameter>
Pid 0x52 show sometimes 2.8%, sometimes 92% when it should be about 20-30%
Pid 0x12F3 shows always 0
With pcmlogger14, if I have both configured, debug log says 12F3 is configured, but it shows value 4.8% for pid 52
MAYBE I have something wrong with sensor or wiring, but I have tested with 2 different sensors and measured wires & voltages multiple times.
Pid 0x52:
https://en.wikipedia.org/wiki/OBD-II_PIDs
52 82 1 Ethanol fuel % 0 100 %
Pid 0x12F3 found by UniversalPatcher
Re: Pcmlogger and Flex Fuel
Posted: Thu May 27, 2021 10:15 am
by aaronc7
0x52 doesnt work on my P59.
0x22139C is Ethanol sensor frequency (1 byte, Hz, no conversion factor)
0x2212F3 is Ethanol Content (filtered) (1 byte, %, x/2.55)
Note that 12F3 is a filtered value. If I had a sensor wired up perfectly into the PCM, and sensor calibration set up correctly, but not enabled in the tune for whatever reason........139C would give me some valid readings but 12F3 would still be zero since the reported value to the PCM is always 0 in that case.
12F3 also has some sort of delay/lag factor and resets to 0 (unless otherwise set in the cal) after a reflash etc, and then will slowly creep up to actual E content value as you idle the engine.
Hope this helps!
Re: Pcmlogger and Flex Fuel
Posted: Thu May 27, 2021 5:21 pm
by joukoy
aaronc7 wrote:0x52 doesnt work on my P59.
0x22139C is Ethanol sensor frequency (1 byte, Hz, no conversion factor)
0x2212F3 is Ethanol Content (filtered) (1 byte, %, x/2.55)
Note that 12F3 is a filtered value. If I had a sensor wired up perfectly into the PCM, and sensor calibration set up correctly, but not enabled in the tune for whatever reason........139C would give me some valid readings but 12F3 would still be zero since the reported value to the PCM is always 0 in that case.
12F3 also has some sort of delay/lag factor and resets to 0 (unless otherwise set in the cal) after a reflash etc, and then will slowly creep up to actual E content value as you idle the engine.
Hope this helps!
Thank you.
Now I have this:
Code: Select all
<Parameter
id="139C"
name="Ethanol Hz"
description=""
byteCount="01"
bitMapped="False">
<Conversion units="Hz" expression="x" format="0.00" />
</Parameter>
<Parameter
id="12F3"
name="Ethanol 12F3"
description=""
byteCount="01"
bitMapped="False">
<Conversion units="%" expression="x/2.5" format="0.00" />
</Parameter>
But both shows zero.
I have made connections using this thread:
https://ls1tech.com/forums/pcm-diagnost ... te-up.html
But looks like gnd & ignition is swapped?
So I changed them like there:
https://motorsport-electronics.co.uk/on ... ensor.html
Still nothing
Maybe sensor get damaged by wrong connection
Edit:
Another sensor works!
No fuel lines connected, reading 49Hz
Re: Pcmlogger and Flex Fuel
Posted: Thu May 27, 2021 7:38 pm
by joukoy
Now 12F3 displays 26%.
Maybe other sensor is defective.
Currently connected is VW sensor from ebay (Continental, Made in Mexico).
It have smaller connector than GM sensors, otherwise it should be compatible (50-150Hz)
Don't know about temperature sensor, or if it's important?
Edit: Temp sensor is working
Re: Pcmlogger and Flex Fuel
Posted: Fri May 28, 2021 12:41 am
by bubba2533
If there is air in the sensor it will read all over the place. I use a Continental sensor and it works just fine. At least for the P59 12587603 OS the fuel temperature isn't used anywhere in the code.
Re: Pcmlogger and Flex Fuel
Posted: Fri May 28, 2021 12:59 am
by joukoy
Maybe I was unclear?
I have now Continental sensor installed and it measures 26% ethanol content.
I have 21 litres E85 + 58 litres E5.
If I calculated correctly, it its 26.3% of ethanol.
So, it is working fine.
Re: Pcmlogger and Flex Fuel
Posted: Sat Jun 12, 2021 8:10 pm
by joukoy
Still something wrong.
With 26% blend, lterm was ~ +10%
Added 36 liters of 5% gas, now 12F3 shows 17.2% which is close to my calculations (16%) => Now lterm is ~ +5%
Why PCM is not commanding more fuel (without lterm change) when have more ethanol?
Re: Pcmlogger and Flex Fuel
Posted: Sun Jun 13, 2021 1:28 am
by bubba2533
Have you changed the delay/transition volume values? They slow down the changing of the flex percent significantly.
Re: Pcmlogger and Flex Fuel
Posted: Sun Jun 13, 2021 8:39 pm
by joukoy
bubba2533 wrote:Have you changed the delay/transition volume values? They slow down the changing of the flex percent significantly.
All flexfuel tables are direct copy from -04 L59 PCM.
I doubt there is so long delays, they have effect after consumed 36 liters gas?
Re: Pcmlogger and Flex Fuel
Posted: Mon Jun 14, 2021 2:16 am
by Stokes1114
My p01 l59 has a transition volume of 0.048 gallons and delay volume of 0.005 gallons.