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Ethanol Content Clamp Function

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The continental Ethanol Content Sensors will read significant lower when low flow goes through the sensor. This means during a WOT run the ethanol content will read significantly lower at high load and rpm than at idle, because the flow in the return line is low. 

I attached a Log to show the problem. With more boost, I see values 20% lower at WOT than at idle.  This is a well-known problem and other ECU manufacturers have an Ethanol Clamp function for a good while.

The Ethanol content does with activated clamp function only update when the Injector Duty Cycle is below a certain level. Once the INJ Duty Cycle is higher than the threshold the ECU takes the last value read below the threshold and update Ethanol content only when InjDC goes below the threshold. So a quite simple function, but with a big need! Please implement it asap. Thank you. 

 

Example_log_why_eth_clamp_function_needed.png

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On 8/26/2018 at 5:46 AM, barge said:

Cobb recommends you install the sensor prior to the fuel rails for just this reason.

Although I believe the clamp function would be worthwhile.

Good in theory, but it becomes a restriction obviously

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That seems to be the main reason people put it after the rails. Really depends on if the 3/8 (I think) lines are a restriction.

I'd like to be able to set custom blend ratios for boost maps and such. I don't want those maps to blend 0-100% but I want all the fuel calcs to 

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BTW is there reason why ethanol content sensor reads 3-5 % lower ethanol content than in reality. Running VP´s C85 race ethanol and Continental sensor reads only 80-81 % ethanol content. Same with pump E85, but 1-2 % lower ethanol content. C85 should be exactly 85%. 

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