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Discussion Starter #1
So i'm not sure this is even a problem, but I'm curious to see what people think.

Setting: 2009 SRT with B-woody CAI and johan tune, Reso delete.

So im cruising along at like 80 MPH on the highway...

I usually let off the gas substantially and it coasts.

As i ease in on the gas to accelerate or maintain speed, for maybe the first 1/8th of the gas pedal, it "sputters". You know the sound the engine makes when you downshift and let the engine slow the car? That's the sound.

It'll sputter for that 1/8th of the gas pedal, then suddenly catch, stop sputtering, and accelerate.

Is this because im feathering the gas? Is there a tranny issue?

The reason im questioning the issue is because besides this, it functions flawlessly...

Any input would be great, thanks!
 

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I don't think that is a tranny issue... Seems like its attributed to the feathering the pedal.
 

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Discussion Starter #3
thats prolly the case... I was just curious if there's a good technical explanation....
 

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Straight Up Beast SON!!!
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I had this issue issue and the problem is you have to much Sprint Booster in the tune. tell Johan you want just a little bit of Sprint booster in it.. When you remove your custom tune or go back to the stock tune you do not see this issue. Whats happening is you will see you AFR gauge go to lean in the high 20"s and then eventually back to low 14"s when crusing....
 

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I have a Volant CAI, Tsat, and a Johan tune and I get the exact same thing. It doesn't bother me, but obviously I don't want to hurt the engine. I don't have a AFR gauge, unless there is one in the Trinity that I don't know about.

I live in a very populated area, so I haven't had a chance to data-log for Johan.

Do you think we need to get this resolved?
 

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I had this issue issue and the problem is you have to much Sprint Booster in the tune. tell Johan you want just a little bit of Sprint booster in it.. When you remove your custom tune or go back to the stock tune you do not see this issue. Whats happening is you will see you AFR gauge go to lean in the high 20"s and then eventually back to low 14"s when crusing....
I had the very same thing happen to me with one of my earlier tune revisions for the 426. If I remember correctly, it was explained to me as 'tip-in-torque' management - essentially the same thing as the Sprint booster mod. As Jose said, just have Johan dial it down some and you should see this eventually go away.
.
 

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Discussion Starter #7
..... ok ima say it...

i dont wanna "dial it down" on my jeep... haha!! am i going to lose performance? It's a little bit of a neusance, but nothing i cant live with unless it's going to hurt the engine....
 

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The Traveler
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I run my throttle booster at 20% in my tune, I don't experience these symptoms. Mods in sig.
 

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Same thing here and yes Johan is aware of it and he can take care of it if it bothers you, but you would prob get use to it, I know I did. I drove it to and from Florida and never it gave it a thought.
And if you notice at least with mine it doesn’t do it when I gas it when the cruise on.

Johan explained it to me in layman terms as the tune being "too aggressive" and that he could correct it if it bothered me, but i like aggressive lol I just wanted to make sure with him that it wasnt something else and he said it wont hurt anything.
 

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Straight Up Beast SON!!!
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I had the very same thing happen to me with one of my earlier tune revisions for the 426. If I remember correctly, it was explained to me as 'tip-in-torque' management - essentially the same thing as the Sprint booster mod. As Jose said, just have Johan dial it down some and you should see this eventually go away.
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I was actually troubleshooting a problem I had at 80 mph exactly, when on the highway my my jeep woul not downshift ciorrectly from 5th to 3rd. Instead it would downshift from 5th and a split second to 4th and then to 3rd. So it felt like someone had hit me from behind and as soon as Johan took the sprintbooster out completely and the problem went away totally. So Johan said he could try adding just a little bit of Sprint booster to my tune and he did and I left it there.... So curreently have a little bit of Sprint Booster and I am happy with it....
 

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Discussion Starter #11
Johan re-wrote my tune already! Haha top knotch as always. Thanks so much for the feedback guys!
 

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I agree that If it doesn't hurt the engine, I'm keeping it in. I don't want to dial back my tune. Anyway, I kinda like the sound it makes when it bogs down.
 

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I had the very same thing happen to me with one of my earlier tune revisions for the 426. If I remember correctly, it was explained to me as 'tip-in-torque' management - essentially the same thing as the Sprint booster mod. As Jose said, just have Johan dial it down some and you should see this eventually go away.
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Gee, what schmuck told you that? ;-)

J
 

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so JuthfloridaSRT8;788163 said:
I agree that If it doesn't hurt the engine, I'm keeping it in. I don't want to dial back my tune. Anyway, I kinda like the sound it makes when it bogs down.
It doesn't hurt the engine but IMHO it is a safety issue. The fix isn't even noticible (other then it doesnt stuble) if you make the right changes.

J
 
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