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G37 7speed transmission reprogram

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Old 01-05-2011, 05:13 PM
  #121  
Almatti
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Originally Posted by sniper27
I'm in the same position. I can't decide if i want to get this reflash or not. I'm at 6500 miles and it is definitely better than when it was new. Still some jerky and lag, but much improved over time. I am due for 2nd service soon, so I'm still debating if i want this done.

God Bless America: Only here do we have such decisions to make. LOL....Oh yes, what to have for Lunch too...

My remaining issue is the hesitation at braking and then quick step on the gas, not always though...
Old 01-05-2011, 05:40 PM
  #122  
slimlma04
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Originally Posted by sniper27
I'm in the same position. I can't decide if i want to get this reflash or not. I'm at 6500 miles and it is definitely better than when it was new. Still some jerky and lag, but much improved over time. I am due for 2nd service soon, so I'm still debating if i want this done.
absolutly the same issue here! quick brake to gas jerks, im hard on the car, but this is a sports sedan, if i would have known all these issues would def have went with 6mt, but do love the awd on the xs
Old 01-05-2011, 10:37 PM
  #123  
kosstick
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Guys sometimes when i decelerate quickly the car clunks into 1st almost like the transmission can't downshift quickly enough ( or rather smooth enough). The clunk to first doesn't happen always and it is usually when i reach 35-45ish then slow down rapidly. Anyone else having this issue?
Old 01-06-2011, 06:05 AM
  #124  
Chico
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Originally Posted by kosstick
Guys sometimes when i decelerate quickly the car clunks into 1st almost like the transmission can't downshift quickly enough ( or rather smooth enough). The clunk to first doesn't happen always and it is usually when i reach 35-45ish then slow down rapidly. Anyone else having this issue?
Welcome to the thread and start reading from the begining.
Old 01-06-2011, 08:59 AM
  #125  
coolraz
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Originally Posted by Chico
Welcome to the thread and start reading from the begining.
Has anyone every experienced somethign similar to this but just the car feeling heavy vs light. Ocasionally when I am driving (on my commute, so same road), and even though I'm driving it in DS, and I hit the gas, it just takes SO LONG to accelerate (like it's not giving full throttle, and yes I know there's WOT restriction but that's not it because other times at same speed it's full gas when I hit it and it just goes). And it's in all gears, so even if I pick a gear manually even a low gear it's the same issue.

When I reset the AFR targets (with the cipher software from Uprev), it seems to go away, but then comes back (it also goes away on its own).
Old 01-06-2011, 09:19 AM
  #126  
blnewt
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Originally Posted by sniper27
I'm in the same position. I can't decide if i want to get this reflash or not. I'm at 6500 miles and it is definitely better than when it was new. Still some jerky and lag, but much improved over time. I am due for 2nd service soon, so I'm still debating if i want this done.
Well I haven't heard of anyone saying it was worse, a couple said not a really significant improvement and a few have said it's much better. I've got 20k on my 09 so I doubt my AT is going to do much more "learning" so I'm going for it next month.

Keep those replies coming after you've got the reflash, it'd be nice to get a consensus.
Old 01-06-2011, 09:19 AM
  #127  
MaluG37
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I've had it clunk into 1st, 2nd and 3rd. Even in Park. But when I bring it to the dealer it all magically disappears. It most frequently happens in stop and go traffic on a slight incline. As previously mentioned, quick transitions between acceleration and braking leds to clunky shifts. But if you pay attention to the shifts I've noticed that when I release the accelerator just as the tranmission is about to upshift or downshift thats when the trans shifts bad. It's hard to avoid this since in casual or traffic driving the car shift 3 times before hiting 25mph and I think 4 is around 35mph. I think the gear hunting that people talk about is the transmission shifting gears at a speed that would normally not require a shift in a 5sp auto.
Old 01-06-2011, 09:37 AM
  #128  
1cleanG
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wowwww, i havent heard of these probs w/ the autos!?
Old 01-06-2011, 02:28 PM
  #129  
Marc Collins
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Originally Posted by Saltin
I've got no idea, but from what I understand it appears to address issues that manifest during D driving. For example in manual mode, I can make my car coast much better than it does in D. To be honest, the real issue for me is the excessive engine breaking when the car should just be coasting, it seems to kick in right around 20-25km an hour. It's annyoing as heck and makes the car's momentum just die. If I could get that addressed I'd be pretty happy - all the other quirks my transmission had disappeared as it adjusted to my driving style over break-in.
That is by design. It mimics a manual transmission. I like it because you rarely need to use the brake pedal in traffic (besides stop lights or stop signs). If you don't want to slow so much, leave your foot slightly on the accelerator as you would in a manual transmission car or a hybrid.
Old 01-06-2011, 02:34 PM
  #130  
Marc Collins
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Originally Posted by bashirdur
The car drives heavy. The acceleration is taking more effort to press down and for the car to take speed. Pretty much every car from the start at lights get ahead of me even if I'm pressing the accelerator down. Its just the ups and Downs with this car I guess
Good, they may have got rid of the ridiculously exaggerated throttle response (80% of the throttle in the first 40% of pedal travel). That alone would look after half of the unnecessary shifts the poor 7AT tries to do because it thinks you're in race mode when you are not.

Proof: the tranny shifts beautifully in Snow Mode.

Last edited by Marc Collins; 01-06-2011 at 02:43 PM.
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Old 01-06-2011, 02:39 PM
  #131  
Marc Collins
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Originally Posted by FishMeetFish
Also, engine braking is much less aggressive after TSB was performed.
That's unfortunate...
Old 01-06-2011, 02:58 PM
  #132  
Marc Collins
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The only issue that doesn't seem opinion/preference-based, from reading this thread, is the lag that occurs when changing from a steady-state speed to needing significant acceleration. Trying to pass on the highway is the classic scenario.

Can those who have had the update done please confirm as soon as possible whether this common issue has been resolved or not? I doubt it will be, because the problem stems from the tranny not knowing how many gears down to shift under a sudden throttle application situation. With only four or five gears total, it's a pretty easy decision. When you get to seven or eight, it's much tougher.

I think they are trying to avoid a situation where you are driving at 50 mph/80 km/h, stuck behind some slow-poke, in 7th gear, of course, for fuel economy reasons, then go to pass and stomp the throttle and the tranny shifts back to 5th gear...but then once you get moving and are accelerating swiftly (but not swiftly enough), it realizes you need to go back to 4th gear. Avoiding the shifting down mid-action is the goal. Unfortunately, that means hesitation at the outset while it figures out what you need/want. The exaggerated throttle response means that even if you floor the throttle, the car was already overreacting from the initial moment you started pushing the pedal. Hence all the reports that the car responds so well when you DON'T floor it. That's because the throttle application is being sent as torque immediately to the tranny, instead of being held back waiting for the tranny to decide what gear to go in to.

I am guessing the "half-way between old mode and Snow Mode" throttle mapping that seems to be what people are describing is the only "fix" for this. And it is't a fix, it just reduces the amount of times or severity of the tranny overreacting to a too-sensitive throttle. You can solve the problem yourself by just applying the throttle more smoothly.

Reducing the responsiveness of the tranny just slightly to downshift based on throttle input should solve the 20 - 40 mph issues.

However, if they took away the relatively aggressive engine braking in the process, then there is nothing sports sedan left in the car. May as well drive a Camry.

I will await more reports from those who update, but the lag and shifting can mostly be resolved by driving more competently/smoothly. You cannot bring back the engine braking no matter what. Therefore, at the end of the day, a dumbing-down of the car that I will avoid.
Old 01-06-2011, 03:34 PM
  #133  
HappyG
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Originally Posted by Marc Collins
You can solve the problem yourself by just applying the throttle more smoothly.
This strategy practically doesn't work in NYC traffic.
Old 01-06-2011, 03:46 PM
  #134  
MaluG37
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I've tried to smoothly apply the throttle and like Fish said in the NYC area its real hard to do. I do like the engine braking, but I don't want so much of it in the D mode. I agree that this is a sport sedan and thats what the DS or manual mode should be used for. I use to drive a manual car and the way this car shifts just isn't right. Then when I try to shift on my own it decides to downshift for me so there's no way out. If this car was offerred with an AWD manual I would have bought that.
Old 01-06-2011, 04:03 PM
  #135  
Mike S.
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So here is the $64,000 question:

What does the TSB say? Other than the very first post saying x, y and z, we don't have any concrete evidence of what the TSB says it fixes.


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