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Discussion Starter · #1 ·
I've been noticing a flutter from either the engine or trans when at speed and coming off throttle. This is happening in and around town mostly and the way I've been duplicating is to get up to normal speed (25-45 mph) give a constant amount of throttle input and then let off the throttle normally (aka: not abruptly). I then get a ever so subtle flutter you can feel transmit from the drivechain into the chassis. I wonder if this is part of that wastegate turbo issue being reported on some of these early models?

Anyone else experiencing this or something similar?
 

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Discussion Starter · #3 ·
Does it sound mechanical or more of the exhaust type sound?
It’s less of a sound and more of a vibration feeling you get through your seat, pedals and wheel. So maybe Flutter isn’t the best way to describe it. It’s like a rapid fire hesitation you feel.

I hate things like this bc it’s hard to describe and I know they’ll only look into it if a tech can feel what I do.
 

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It’s less of a sound and more of a vibration feeling you get through your seat, pedals and wheel. So maybe Flutter isn’t the best way to describe it. It’s like a rapid fire hesitation you feel.

I hate things like this bc it’s hard to describe and I know they’ll only look into it if a tech can feel what I do.
I have noticed the same thing a few times when letting off the gas. It reminds me of when the A/C would kick on for the first time in my old car where I would feel the vibration of it through the pedal and the RPMs would dip for a second as the new load is put on the engine.

One way to test it would be to turn off the A/C then turn it on while driving and see if you notice it.
 

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Would you describe it like this? From a post I did a while back:

https://www.ascentforums.com/forum/...ckage-23-8-passenger-georgia-2.html#post22895

"I wouldn't say it's dead and then boost. Turbo 4's do feel different than a natural V8. You'll have to learn to tip in the throttle differently. No bad. I do think this thing hits full torque at like 2000 rpm. It pulls really well once it's rolling. Especially like highway over takes. I was shocked how well it did considering it's girth.

One other thing I've noticed is what I think is compressor surge on mid throttle or high load with light throttle tip ins. Kinda feels like a shutter for the easiest way of describing it. Betting Subaru re-maps that out at some point which will stink because they'll probably advance timing, fuel and pull boost. I don't mind but 80% of people from non-turbo cars won't like it."
 

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I agree with the descriptions "fludder" or "shutter". I've experienced it mostly when the vehicle is cold after sitting overnight. I agree that it happens for me in the 25-35 mph range. It's as if there's a hesitation or it's like the vehicle's struggling to find the right gear. Maybe it's just normal for CVTs? There's no mechanical noise or grinding or anything like that. I agree with the description that it's something you feel in your seat.
 

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Discussion Starter · #7 ·
Would you describe it like this? From a post I did a while back:

https://www.ascentforums.com/forum/...ckage-23-8-passenger-georgia-2.html#post22895

"I wouldn't say it's dead and then boost. Turbo 4's do feel different than a natural V8. You'll have to learn to tip in the throttle differently. No bad. I do think this thing hits full torque at like 2000 rpm. It pulls really well once it's rolling. Especially like highway over takes. I was shocked how well it did considering it's girth.

One other thing I've noticed is what I think is compressor surge on mid throttle or high load with light throttle tip ins. Kinda feels like a shutter for the easiest way of describing it. Betting Subaru re-maps that out at some point which will stink because they'll probably advance timing, fuel and pull boost. I don't mind but 80% of people from non-turbo cars won't like it."
Yup thats probably the same thing im feeling. It's just something I noticed and my wrx does not do this. I'm thinking you are correct and a re-map will fix this in the near future. I'll mention it when we go in for the first oil change to get it documented.
 

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I could invoke the same feeling on my CVT WRX. Is your WRX a stick?

Yup thats probably the same thing im feeling. It's just something I noticed and my wrx does not do this. I'm thinking you are correct and a re-map will fix this in the near future. I'll mention it when we go in for the first oil change to get it documented.
 

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I notice this also but seems like pulls from stop through first "gear" and then in second "gear" there's a dead spot briefly and then pulls normal. I thought it might be torque converter locking up and discounted it.
 

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Feels to me like the CVT trying to pretend it's an automatic and do a fake shift. I haven't yet felt it when I am forcing a gear range, but, I haven't extensively tried it yet either to rule it out.

I'll do so tonight.
 

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TC should be locked around 15 I think, if it's anything like my Outback.
 

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Discussion Starter · #12 ·
I wonder if this is a CVT thing now that others have mentioned it... ive never noticed it on any other Subaru CVT's though so either it wasn't happening or wasn't as pronounced.
 

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I get the same sort of thing at those speeds when letting of the throttle. The CVT can't seem to figure out what gear to pick. I don't think its an actual CVT issue, but rather the car trying to simulate a shift. I am hoping that they do update the shift curves down the road.
 

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Discussion Starter · #14 ·
I get the same sort of thing at those speeds when letting of the throttle. The CVT can't seem to figure out what gear to pick. I don't think its an actual CVT issue, but rather the car trying to simulate a shift. I am hoping that they do update the shift curves down the road.
Since its all programmed shifts im sure a software update is possible to fix it.
 

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Ok, not sure if what I’m experiencing is this, or not. But reading the posts, maybe??

Today, while pulling out of a parking space... I felt & and heard a growl... almost like a boat exhaust. I was able to duplicate in lower speeds / gear... but once above 25 it went away.

I’ll do more testing, tonight, see if I can record the sound.
 
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