I was driving yesterday in dynamic mode. I accelerated while making a turn, and the car failed to upshift. Instead, it stayed in gear and revved really high. I thought that I may have accidentally put it into manual shift mode, but I checked, and this was not the case. I let the RPMs settle down, and tried again, but it did the same thing. Fortunately, there wasn't any traffic around, so I pulled over and brought the car to a stop. I put it in park and then back into drive again, and then it was fine. Thank god this didn't happen to my wife. She would have really freaked out. Has anyone else experienced something like this?
First significant mechanical glitch. Car fails to shift gears when accelerating ...
gweempose
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I was driving yesterday in dynamic mode. I accelerated while making a turn, and the car failed to upshift. Instead, it stayed in gear and revved really high. I thought that I may have accidentally put it into manual shift mode, but I checked, and this was not the case. I let the RPMs settle down, and tried again, but it did the same thing. Fortunately, there wasn't any traffic around, so I pulled over and brought the car to a stop. I put it in park and then back into drive again, and then it was fine. Thank god this didn't happen to my wife. She would have really freaked out. Has anyone else experienced something like this?
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Did your car seems to accelerate by itself without changing gear?
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This has also happened, in very few and random cases, in the V60 r-designs I had as company cars plus the current car (S80 T6); only when I was in Sport mode (which is virtually all the time).
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Pretty sure that's just the transmission holding a gear. Many automotive press/enthusiasts love cars that do that since it's good for sporty driving (though admittedly, less useful on an SUV like the XC90). Just put the transmission back in normal/eco and the transmission is very quick to upshift.
No, the car was not accelerating by itself. I noticed the problem right away because of the engine sound. A quick glance down at the tachometer confirmed it. It was revving way higher than it's supposed to.
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The reason I asked is because we had a problem with our car before, it revved by itself without me pressing the accelerator and seems to be stuck in a specific gear. Anyway, I hope it was just a glitch or something and it doesn't happen again.
WITH GVs post, im confused whether this is is a glitch or not.
Holding a gear is normal for a vehicle in sport/dynamic mode.
Accelerating or revving on its own is not normal.
Accelerating or revving on its own is not normal.
Mine also has done this a few times. I dont think it's normal, cause it doesn't do it all the time.
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I noticed the same in dynamic mode on and off, usually when I am slowly pulling off from stop or making a turn ( very light throttle). The car holds 1st gear till 4-5 k and then downshifts. This is not normal or expected behavior and is a software or hardware flaw that needs to be addressed ( to clarify, the car is not accelerating, only high revving).
If at 1st gear, 4k RPM, the speed is around 20mph, then it is not downshifting.
If speed is below 15mph or even lower, it may be more than downshifting problem. Maybe the transmission decided to not engage for some reason.
I've had this happen in sport mode in my g35 sedan ... automatics don't do good in sport mode in my opinion, it's great if you want to get up and go, I was always more of a fan of the kick down by stomping on the gas for a quick second forcing it to downshift. Actually next time it does it try stomping on the gas all the way down for a quick second the computer won't let it downshift but it might kick it out of it's brain fart. Or have you tried taking it out of sport mode to comfort see if that does it.? Just a thought
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Unfortunately - yes. This has now happened three times to me. Vehicle is XC90 T8. Details:
- hybrid mode
- gear selector in B
- starting from full stop
- engine had just started
- 90 degree turn into traffic
Second time car had been sitting outside for 2+ hours, cold weather as noted above. 75% battery remaining - hybrid mode shifter in B. Vehicle started motor - proceeded to exit parking lot. Made 90 degree turn to the left and accelerated under gas power - would not shift out of first gear. Took foot off accelerator and fiddled with shifter - back in B and accelerated OK. Was in traffic and in ability to accelerate impeded traffic flow.
Third time leaving work. 25% battery remaining - car started engine and I proceeded out of parking lot to state highway. Made 90 degree right-hand turn into 40+ MPH traffic - car would not shift out of first gear. Used gear selector to go to N and then D and car resumed and shifted normally.
I'll probably write something up in the Volvo support forums - as unsure what to do when this happens - and depending when it happens it could be a dangerous situation.
Yep. Sounds exactly the same as what happened to me. Fortunately, I haven't experienced the problem again, but it's still very concerning nonetheless. I agree that it could be very dangerous in certain situations. For example, if you were about to make a right turn on red but needed to accelerate quickly because of traffic approaching.
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Ah - two more times. But I think I have figured out why - and will try to duplicate / determine more tomorrow.
The XC90 T8 has the crystal shifter - it is electronic, not mechanical. Normally I have the car in Hybrid Mode - and use the shifter to choose B (which does breaking and engine battery charging - otherwise the same as D). To get into the B mode I pull the shifter back (rapidly) a few times - which should step through: R N D B.
But today I noticed that in addition to the driver's display showing the B and Hybrid ... that to the left of the letters was the number 1. (It actually looks more like a vertical white line versus a number.) And of course - car would accelerate but not shift into second gear.
Pressing forward on the crystal shifter the 1 disappeared - and another press I was into D mode. Then pull back - in B and all is well.
I'm going to guess that I got the car into manual gear shifting mode (without knowing it / not intentionally). Its quite possible that this same thing can happen in the XC90 T6 with the mechanical gear shifter.
I find it difficult to believe that if you had it in first gear, that it would stay in 1st gear and allow you to redline the car indefinitely. My bmw will shift automatically if the rpms get too high (or too low), despite being in manual/sport mode, to protect the engine/transmission.
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When the PHEV T8 is in hybrid mode there is no tach on the display - so have no idea where redline is ... I wouldn't push it that far anyway. Was probably up to 15-20 MPH (24-32 km/h). I could change the mode (to one that does display the tach) but my experience it that changes a lot of things (and may pull it out of first gear as well).
Every time this has happened to me (except the once on my street) I've been on a road with traffic - so not the kind of place to experiment. Maybe when I have more time this weekend I'll find some open space without other drivers and look at this in more detail (including whether it will shift into second).
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