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Hello I have tuned 2014 3.5l Ford Flex. Nice gain 50 HP and 40 nm of torque. Around 15 PSI of boost 0.85 WOT lambda 8.5 spark advanced. There are wideband o2 sensor mounted, so I was thinking to force a little bit leaner fuel mixture on the light load but I really don t know how. I was trying to force open loop cold table by setting very hight ECT and lambda temperature value but Flex still want lambda 1. How to force lean mode best in CL ? Can I change the stoichiometry value ?
Best regards.
i was wondering the same thing, I would think you could use the stoich value to lean it out a bit as long as you watched the krQuote:
Originally Posted by Cawe
But I can t find that option in the definition. Stoich AFR setting in the general tab, change only calculations in VCM not in the vehicle. I see that F150 definition has all of that options but I don t know how to use it in Flex.
The "Stoich" value is just purely for fuel volume calculations. The closed loop system works off Lambda so the stoich value of the fuel is irrelevant aside from the fuel calcs.
Not sure if there is an available commanded closed loop lambda table for part throttle, and even then you won't see too much of a gain from lean cruise due to the torque dropping off as afr is leaned out. I would focus more on optimizing the cruise ignition and cam timing, if possible. In some setups you can retard the intake cam to the point that you have a makeshift atkinson cycle where you will have the piston pushing some of the air/fuel charge back into the intake prior to the valve closing, thus reducing the effective displacement.
This is all theory though, and your mileage may vary :cheers:
Not sure on Ford's Bosch control implementation, but in the VW/Audi world it's hard coded to 1.0 lamba and is not easy to change... Many have tried.
I'm fairly sure it'll be the same on Ford, save for an unmapped table or scalar that I'm unaware of.
There is a scalar in F150 definition. Let s see I attached the file.
your ford flex file has it also under fuel tab/general/ stoichemetry this is what i change to run ethanol mixtures. But like Evo8john said, im not sure if it will make a difference. change it to 15 and see what it does lol i know my e85 tune just rips through fuel! 19 mpg on the hwy with a 2.0 running 70-80 mph i advanced my timing under cruise conditions to help it do a little better on the gas mileage. good luck and keep us postedQuote:
Originally Posted by Cawe
I was able to add that parameter (that the F-150 has) via User Defined Parameters on my MKT but I haven't tested it yet. I can probably add it and make the change to your file if you want to try it out.
jr2185 if you have any free time please make it. I will try. Stevekreger It doesn t change antything. I change only calculations in VCM program not in PCM.
[ECM] 11960 - Default Target Lambda: The default commanded lambda to use.
[ECM] 11269 - Minimum Target Lambda To Remain In Non-Stoich Closed Loop: The minimum target lambda to remain in non-stoich closed loop control. Below this value will force open loop fueling.
[ECM] 44168 - Cylinder Cutoff Lambda Limit (Catalyst Protection): This is the commanded lambda limit value when torque control requires fuel enleanment to reduce torque. It will be used only if higher than all other lambda targets, and lower than the combustion stability lambda limit.
[ECM] 44169 - Cylinder Cutoff Lambda To Achieve Desired Torque Reduction: This is the commanded lambda translation based on the desired torque reduction ratio. It is used when torque control requires fuel enleanment to reduce torque. It will be used only if lower than all other lambda targets, and higher than the catalyst protection lambda limit.
[ECM] 44171 - Cylinder Cutoff Lambda (Combustion Stability) Temperature Compensation: This is a temperature compensation for the commanded lambda limit for combustion stability.
[ECM] 11961 - FMEM Target Lambda: The commanded lambda to use when a system failure is present preventing proper operation. This is caused by a failing oxygen sensor, or an injector fault.
[ECM] 12127 - FMEM Target Lambda (Second Fuel): The commanded lambda to use when a system failure is present preventing proper operation. This is caused by a failing oxygen sensor, or an injector fault. Flex Fuel / Bi-Fuel.
[ECM] 12140 - Manual Fuel Override: Allows the target lambda to be overridden by the calibration.
[ECM] 32892 - O2 Closed Loop Bias Cat Temp vs. Airmass - Bank 1: The closed loop bias voltage for the Bank 1 O2 sensor. Positive values are richer, negative values are leaner.
[ECM] 32894 - O2 Closed Loop Bias Cat Temp vs. Airmass - Bank 2: The closed loop bias voltage for the Bank 2 O2 sensor. Positive values are richer, negative values are leaner.
I think the most important are :
[ECM] 11960 - Default Target Lambda: The default commanded lambda to use.
[ECM] 44168 - Cylinder Cutoff Lambda Limit (Catalyst Protection): This is the commanded lambda limit value when torque control requires fuel enleanment to reduce torque. It will be used only if higher than all other lambda targets, and lower than the combustion stability lambda limit.
Do you have the User Defined Parameters feature so you can use the .xdf, or should I modify the file for you? And is your file the Flex file posted above and the one you want modified?Quote:
Originally Posted by Cawe
Here is the Flex file with default lambda set to 1.05. Let me know if it works. This parameter is defined in SCT as "Open Loop Lambse Default" but it's the same parameter as HPT "[ECM] 11960 - Default Target Lambda: The default commanded lambda to use" in the F-150 file.
Attachment 118850
Unfortunetly i don t have User Defined Parameters feature. I attached the latest tune. The last one was the stock one. Thank you very much for your time.
Attachment 118851
Here is the change to that file.Quote:
Originally Posted by Cawe
Attachment 118852
I just tested that parameter on my MKT. It didn't make a difference. Still ran at Lambda 1 with it set at 1.05.
I've done this on some other stuff and it worked. On NA I don't really go past .33 load and let it fan in to 1 at .4
I wouldn't push it over .45 load max imo.
CoreyMS what parameter did you change ?