Flex fuel Hellcat limits

2016 Hellcat 7/16 build date
2.75 upper
ATI 10% lower
2" ARH headers no cats
170 tstat
BWoody intake
BAP
FIC 1200's
HP tuners flex fuel OS.

Not my first Hellcat, but first with the flex fuel OS. Having trouble with the throttle not opening all the way until 4000 rpm, the bypass valve not shutting all the way limiting boost and not getting power enrichment. The "throttle tq source" toggles back and forth from "pedal to "overtemp". It will do this even when the car is cold after sitting overnight. Wondering if anyone else has ran into this with the flex OS?

Attachment 75888

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Quote:

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Originally Posted by 32vape

2016 Hellcat 7/16 build date
2.75 upper
ATI 10% lower
2" ARH headers no cats
170 tstat
BWoody intake
BAP
FIC 1200's
HP tuners flex fuel OS.

Not my first Hellcat, but first with the flex fuel OS. Having trouble with the throttle not opening all the way until 4000 rpm, the bypass valve not shutting all the way limiting boost and not getting power enrichment. The "throttle tq source" toggles back and forth from "pedal to "overtemp". It will do this even when the car is cold after sitting overnight. Wondering if anyone else has ran into this with the flex OS?

Attachment 75888

Attachment 75889

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Based on the throttle torque source toggling to overtemp intermittently, it sounds like you need to reevaluate your Exhaust Gas Temperature and Catalyst Protection tables, especially since you don't have cats to worry about. Not sure this will solve all your problems, but it could be a good start.

Do you not shut it off or did you forget? Still stock target temps. Looked at all of it you lowered cat temp table so I'm at a loss other then tables missing and just raise cat targets to disable.

https://www.hptuners.com/forum/showt...nt-in-3rd-gear

I know your not seeing the same issue other then OT coming up in log limiting stuff. I am about to dive into the flex part in the next week or so and have not had this issue. Other then when the targets are not maxed it does funky stuff like the post listed.

Quote:

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Originally Posted by 32vape

2016 Hellcat 7/16 build date
2.75 upper
ATI 10% lower
2" ARH headers no cats
170 tstat
BWoody intake
BAP
FIC 1200's
HP tuners flex fuel OS.

Not my first Hellcat, but first with the flex fuel OS. Having trouble with the throttle not opening all the way until 4000 rpm, the bypass valve not shutting all the way limiting boost and not getting power enrichment. The "throttle tq source" toggles back and forth from "pedal to "overtemp". It will do this even when the car is cold after sitting overnight. Wondering if anyone else has ran into this with the flex OS?

Attachment 75888

Attachment 75889

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You ever figure this out?

I started working my way back to stock on tables I had changed. The max timing table was the one. I had it just maxed in all the cells. I set it up so it more closely resembles the actual torque curve from the dyno. All is good with the throttle and bypass valve now. Still trying to get the flex fuel figured out. I copied the flex fuel data from a 2017 Chrysler Pacifica cal, and then a 2016 Chrysler 200 v6. It will read up to 52% on the scanner with verified 85% in the tank. Can't get it to read any higher even with the fuel trims adding.

Quote:

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Originally Posted by 32vape

Still trying to get the flex fuel figured out. I copied the flex fuel data from a 2017 Chrysler Pacifica cal, and then a 2016 Chrysler 200 v6. It will read up to 52% on the scanner with verified 85% in the tank. Can't get it to read any higher even with the fuel trims adding.

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I may be wrong, but the file you posted above does not appear to have the "Flex Fuel Patch" in the "OS tab applied. Usually when a patch is applied, the option to apply is diabled. Not sure if this would cause the conditions you are seeing, but it is something I noticed.

You ever get it to read past 52% ?

Got the flex fuel working good now. The goal voltage offset and goal FAR offset for the widebands is not even close with the way it's populated from the start. Any of the tables that had a weird y axis needed changes. For example, the goal FAR offset y axis was setup like this:

85
90
0
0
0

I rescaled it and came up with values based on the change in stoic from e10 to e85.

Are you willing to share your progress with this tune?

Find out what the stoich far is for the given percentages you want to map and subtract the stock FAR from it and put that in for the offset. Example 0% .0680-.0720 = -.0040 so for 0% it is -.040 its really that simple. Stock tune would not idle at 1 lambda when setting stoich to .0680 because they did not have offset tables back in the day for hellcats at least I didn't see them before all this flex stuff got opened up.

Quote:

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Originally Posted by JoshCP527

Find out what the stoich far is for the given percentages you want to map and subtract the stock FAR from it and put that in for the offset. Example 0% .0680-.0720 = -.0040 so for 0% it is -.040 its really that simple. Stock tune would not idle at 1 lambda when setting stoich to .0680 because they did not have offset tables back in the day for hellcats at least I didn't see them before all this flex stuff got opened up.

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What about the Goal Offset how is the voltage figured ? it out I get the Goal FAR Offset