Anybody else feel funky downshift while sitting at a stop light?
- Thread starter CC58
- Start date
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- 23 CX-5 Premium
The only time I feel what you're talking about is slowly climbing my driveway into the garage. You can feel the transmission switch back to torque converter operation because I'm under 5 mph and pulling a grade. This is exactly what it's supposed to do. But sitting full stop at a light I would think the transition would be much smoother (as in imperceptible!).
After coming to a stop at a stop light and sitting, tranny is completely disengaged to save gas. If you lift off the brake pedal slightly you can feel it re-engage so that it's ready to creep or accelerate as needed, that might be the little bump you are feeling (I certainly could feel it).
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- 23 CX-5 Premium
That's why you can trip the trans up slightly by transitioning from brake to throttle too abruptly from a dead stop. You can make it "hiccup" a bit.
robertmazda
Member
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- 2013 CX-5 Touring
I've felt it a number of times when fully stopped. I've actually looked back to see if someone slightly bumped me - that's what it feels like to me.
I had the same problem, happened twice. I too looked to see if someone hit me from behind. It was violent enough to send my head back into the headrest. Complained to dealer at my last oil change and they performed the following:
"Verified slow trans engagement. Updated TCM and PCM calibrations. Road tested and system passed. Symptom CD:80 Damage CD:9
Problem has not occurred since.
"Verified slow trans engagement. Updated TCM and PCM calibrations. Road tested and system passed. Symptom CD:80 Damage CD:9
Problem has not occurred since.
L
L7D4R
It's not just the CX-5's that lurch forward like that. My '06 Tacoma use to do it from time to time as well. In fact it seems to be a common thing across brands/ model years...
Google... "car lurches forward while stopped"
Google... "car lurches forward while stopped"
Happens daily... at least once or twice in my commute. Come to a complete stop at the light, firmly place foot on brakes, sometimes you will feel something that feels like a "downshift". It's as if the transmission is fully disengaging, but slowly. It's pretty unique feeling. I've never felt it quite like this in any other cars we've owned with an automatic. And what's interesting is, at least in my car, it feels like the engine smoothes out, like I shifted into neutral or park. So I just think that the transmission is disengaging when you come to a full stop.
I'll have to watch for it.... nothing has really stood out on mine.
I thought the same thing when it happened to me the first time. Its fairly gentle though ,to me the vehicle doesn't see to lurch forward as mvan described. It looks as the torque converter disengages to full neutral as the idle feels smoother afterwords. I have to test the other theory that the bump is caused by the TC re-engaging due to easing of the brake pedal.
Anyone have proof that the transmission disengages while in drive at a stop or is this just an assumption? I can't detect anything like this on mine and I've been paying attention since I read this thread a while back. I'll stare at the tachometer needle and it's as steady as can be.
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- 23 CX-5 Premium
I thought the same thing when I saw that comment here. If that were the case, why is it you can feel the drivetrain straining slightly to move the vehicle as you decrease pressure slightly on the brake? This torque converter functions pretty much the same as any other, it's use is just far more limited than in a conventional TQ automatic.
After everything is at operating temp, while stopped in D for a short time with no AC on, try shifting into N and see if you can tell that the drive train unloads - I can't which indicates to me that it is already effectively in N since that is what the design logic says it does...
Curious! I tried that too and the tach does move up as the engine is unloaded. I'll see if I can find my manual because I'm curious about this but have my doubts.
pjensen641
Member
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- 2013 CX-5 AWD Touring Zeal Red
I've felt it too. Had the same initial thought that someone tapped my rear bumper very lightly. Never enough to make my head move or anything. Looking back, it is normally when I have been holding the brakes with a very light pressure at a stop. I may have to investigate the theory about the tx going to neutral when the brakes are held with sufficient force.
dragonteeth
Member
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- '15 CX-5 Touring AWD w/ Bose ★
Yup... this is exactly how it feels like for me as well.
