E38/67 Custom OS Addition?

[LSxpwrdZ]

I was wondering if it would be possible to apply a patch to the E85 portion of the OS's so that when a 12v signal is applied to the alcohol sensor input that it shows 85% ethanol. I don't think this code patch is that hard to do and only requires a few of the ethanol switches in the calibrations to make it function. This would really open up the doors for the guys bound to the Gen4 architecture.

Pretty please with sugar on top?

[DSteck]

The alcohol content is based on a frequency input. Not a solid 12 volt. You would need to generate a 150 Hz logic level signal.

[Chris@HPTuners]

i can add the parameters needed, but as stated you need to drive the input with a 0-5V 50-150Hz PWM signal.

Chris...

[DSteck]

I have the technology. I can build it.

Chris, if I give you my OS ID could you add it on mine? I can build a signal generator and verify operation.

[LSxpwrdZ]

It can be done with a 12v signal... I'm not sure if there is a software patch that allows this or what. I do know that you have to select a switch in the OS to a physical sensor for it to work. I've done this on a ZR1 already.

[bbrooks98]

I"m all over this! Whatever you do, allow it to also be used with an actual flex sensor too not just a 12v switched input.

[Chris@HPTuners]

It can be done with a 12v signal... I'm not sure if there is a software patch that allows this or what. I do know that you have to select a switch in the OS to a physical sensor for it to work. I've done this on a ZR1 already.

if you have a file with it done email it to me.

[DSteck]

How does applying 12v to a 5v input not completely wreck it, especially when it is looking for a frequency trigger?

[LSxpwrdZ]

Chris I will see what I can do... It will have a Vin/OS mismatch

[Chris@HPTuners]

Chris I will see what I can do... It will have a Vin/OS mismatch

no probs.

[Chris@HPTuners]

I have the technology. I can build it.

Chris, if I give you my OS ID could you add it on mine? I can build a signal generator and verify operation.

post it up.

[DSteck]

Stock OS and custom OS (I run custom).

I'll have to pin my PCM, but BFD.

[Chris@HPTuners]

Stock OS and custom OS (I run custom).

I'll have to pin my PCM, but BFD.

added to 2.23.880 or later for 12614682.

So here's what you need to know:

1. you have 2 PIDs to log:
- Alcohol % (SAE)
- Fuel Composition (Hz)

2. Spark, the params of interest are:
- Flex Fuel Spark (this is multiplied by the below then added to spark). It can be positive or negative so you can do all kinds of interesting stuff.
- AFR Correction Mult vs. Composition (this is used for all gas/alcohol spark blending Flex FUel Spark and PE/COT Spark) - typical numbers here are 0, 0.25, 0.5, 0.75, 1.0 (cals that are all 0's need to be fixed up)

3. Fuel params:
- open loop tables and PE tables on newer OS's blend between gas and alcohol tables using blend factor below
- blend factor 0 is gas table, 1 is alcohol, 0.5 is middle, you get the idea. (usually this has values in it, again fix if all 0's)
- Note: if your stoich table has a flex fuel cal in here you need to set it to something constant across the whole table (ie. gas numbers) otherwise as you change the freq, the stoich will change.
- obviously you need to be open loop for the fuel stuff to work.

I don't know which pin the sensor input is on the ECM, sorry!

Let me know how it goes.

Post up other OS's and i'll add them first. Once we're all happy it works i'll start the process of adding to everything.

Chris...

[DSteck]

It's pin 40. I'll have to get the parts to add it and breadboard a generator, but it shouldn't be a big deal. Fuel temperature doesn't get used, right? If its not important to anything, I'll force a 2ms on time for all frequencies.

[LSxpwrdZ]

I am using C1-Pin 02 on the E67 I'm using and it was my understanding that it was C1-Pin 05 on the E38?

Chris I will get you the file sometime tonight. Work schedule has been crazy and I've not been able to get over to the shop to get the file for you yet.

[DSteck]

I am using C1-Pin 02 on the E67 I'm using and it was my understanding that it was C1-Pin 05 on the E38?

Chris I will get you the file sometime tonight. Work schedule has been crazy and I've not been able to get over to the shop to get the file for you yet.

That's not the actual flex fuel sensor input pin.

[LSxpwrdZ]

Hmm... I don't have the full pinout description so now I'm wondering what the pins I'm using actually are...

[DSteck]

It's something the other guys have enabled with a modified operating system. Totally different concept.

[LSxpwrdZ]

Makes sense now...

[bbrooks98]

How does applying 12v to a 5v input not completely wreck it, especially when it is looking for a frequency trigger?

The flex sensors use 12v. What makes you think it's looking for a 5v?