15 Coyote W/ Roush Supercharger on E85 Idle Hang-

Hey Guys!

Hoping to see if i can get some help-- We are tuning a 15 mustang coyote with a Roush Supercharger-- on pump gas its great-- on e85 it makes great power but it has acquired an idle hang--
you can just be sitting there in neutral and it will slowly work its way up to about 1800-2000 rpm and hang there- it will then randomly come down back to normal idle but then repeat the process back up to 1800-2000 rpm-- you can burp the throttle and it will come down but then just go back up--- JLT Intake- FIC 1000s Roush Phase 1 Kit with VMP 79MM pulley-- Literally the car runs great makes 700WHP on E85 but this is the only issue-

ONLY does this on Ethanol!

Has any one experience this before?

Appreciate the help in advance!

Trying to upload or attach a file but its not working, so i will continue to try

Hi

Gotta the same setup and throttle hanging on ethanol did you find the table to dial in to cure it

Thanks

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Originally Posted by beyond-redline

Hey Guys!

Hoping to see if i can get some help-- We are tuning a 15 mustang coyote with a Roush Supercharger-- on pump gas its great-- on e85 it makes great power but it has acquired an idle hang--
you can just be sitting there in neutral and it will slowly work its way up to about 1800-2000 rpm and hang there- it will then randomly come down back to normal idle but then repeat the process back up to 1800-2000 rpm-- you can burp the throttle and it will come down but then just go back up--- JLT Intake- FIC 1000s Roush Phase 1 Kit with VMP 79MM pulley-- Literally the car runs great makes 700WHP on E85 but this is the only issue-

ONLY does this on Ethanol!

Has any one experience this before?

Appreciate the help in advance!

Trying to upload or attach a file but its not working, so i will continue to try

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That's interesting, I have a 2015 NA car that does the same thing randomly. throttle body is stock with no changes to the calibration. Id assume yours has a twin 62 throttle though. so your case is interesting.

post a log and tune if possible, thats the only way youre going to get any decent help.

I have a 2016 Procharger car, stock tb, doing the same exact thing. This has to be a somewhat common issue that someone has a solution to, hopefully the chime in.

Try reducing the predicted throttle angle

Before you start your car, with key on: Slowly push the throttle all the way to the floor, then slowly back out. Repeat 2 more times. You should only have to do this once after you flash the car.

Also what made the fix permanent for me is Under Airflow, Electronic Throttle, set Threshold Adder to 360.

Quote:

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Originally Posted by Ranger Coyote

Before you start your car, with key on: Slowly push the throttle all the way to the floor, then slowly back out. Repeat 2 more times. You should only have to do this once after you flash the car.

Also what made the fix permanent for me is Under Airflow, Electronic Throttle, set Threshold Adder to 360.

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Did this work for anyone? I had a bunch of PM's but no responses if it worked or not.

Quote:

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Originally Posted by Ranger Coyote

Did this work for anyone? I had a bunch of PM's but no responses if it worked or not.

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I had a customer try that and it so far has worked for him, he hasnt had any issues. I wonder if its only certain strategies, I put all 15+ on flex fuel unless they ask otherwise, and his is the only one that has ever done that, and only when he's on e85 its really weird, but so far its all good.

It happens on FSGP1A2 (stock strat) and my roush cal also, MGMCAL7 2016 GT with the 727 kit

I know this is an old thread, but I'm having a very similar issue. 2016 GT with Rouch s/c. It runs great while under throttle, but push the clutch in and rpms climb to 2000. popping the throttle doesn't seem to help most of the time ( once in a while, it will drop to 1000, but then back up again). Any time i'm chasing this ghost in the garage, i can unplug the MAF and it will idle down the the normal 750.