[Axylus]

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Driving an automatic here. Just did the 1200 mile service last Tuesday.

In efficient mode, Has anyone noticed a delay in downshifting when braking and then immediately stepping on the throttle? It stalls at a higher rev (3k) and doesn’t downshift when braking. Takes about 3-5 seconds before it goes down a gear while slowing down. This happened for the first time thing morning

The same goes for when driving in sport+ when driving down a hill where the revs kept going up to near 6k but wouldn’t downshift when braking and kept stalling. This going at ~40 mph. This happpened once as well since

Should I be concerned? Or is the car anticipating some sort of rapid speed increase which is why it is stalling?

[M2siast]

Originally Posted by Axylus

Driving an automatic here. Just did the 1200 mile service last Tuesday.

In efficient mode, Has anyone noticed a delay in downshifting when braking and then immediately stepping on the throttle? It stalls at a higher rev (3k) and doesn’t downshift when braking. Takes about 3-5 seconds before it goes down a gear while slowing down. This happened for the first time thing morning

The same goes for when driving in sport+ when driving down a hill where the revs kept going up to near 6k but wouldn’t downshift when braking and kept stalling. This going at ~40 mph. This happpened once as well since

Can we use “stall” for anything other than the engine shutting off?

I didn’t understand your first case because it sounds like the engine turns off at 3k rpm.
In your second case it sounds like you are expecting the car to downshift when it’s doing 6k rpm. If that’s the case, the car can’t downshift because it won’t money shift itself.

Maybe I misunderstood everything.

[M_Power Rob]

Originally Posted by Axylus

Driving an automatic here. Just did the 1200 mile service last Tuesday.

In efficient mode, Has anyone noticed a delay in downshifting when braking and then immediately stepping on the throttle? It stalls at a higher rev (3k) and doesn’t downshift when braking. Takes about 3-5 seconds before it goes down a gear while slowing down. This happened for the first time thing morning

The same goes for when driving in sport+ when driving down a hill where the revs kept going up to near 6k but wouldn’t downshift when braking and kept stalling. This going at ~40 mph. This happpened once as well since

I have not noticed any issues like this (I am only at 600 miles so still driving in break-in mode). To confirm/clarify, you have an 8AT and the car was stalling, literally, wherein you had to restart the engine?

[Axylus]

Apologies for my use of stall. I didn’t know know that it meant the engine turning off.

I meant that the engine will continue holding the rev despite my expectance that it will drop in revs and upshift or downshift

[M2siast]

Originally Posted by Axylus

Apologies for my use of stall. I didn’t know know that it meant the engine turning off.

I meant that the engine will continue holding the rev despite my expectance that it will drop in revs and upshift or downshift

Because the transmission turns with the engine (so 3k rpm in a certain gear will always be the same speed), and you’re reporting the engine maintaining RPM while changing vehicle speed, could you be experiencing the throttle blip of the gear shift assistance (auto-rev match)?
I’m not sure if it’s something that can be turned off in an auto.

Could it be that? Car slows down, but revs go up slightly before engaging a lower gear?

Not sure. Second thought is: was the oil really cold? I think the car will not shift to high rpms when the engine is super cold.

Brainstorming here. I have no idea.

[Axylus]

Originally Posted by M2siast

Because the transmission turns with the engine (so 3k rpm in a certain gear will always be the same speed), and you’re reporting the engine maintaining RPM while changing vehicle speed, could you be experiencing the throttle blip of the gear shift assistance (auto-rev match)?
I’m not sure if it’s something that can be turned off in an auto.

Could it be that? Car slows down, but revs go up slightly before engaging a lower gear?

Not sure. Second thought is: was the oil really cold? I think the car will not shift to high rpms when the engine is super cold.

Brainstorming here. I have no idea.

What you wrote in the second paragraph, “could it be…” is what I am experiencing.

Regardless, if I am driving an 8AT, it should be idiot proof right?

I did a bit of research on your term, “money shifting” from your original post and that’s probably what is being prevented

[M2siast]

Originally Posted by Axylus

What you wrote in the second paragraph, “could it be…” is what I am experiencing.

Regardless, if I am driving an 8AT, it should be idiot proof right?

I did a bit of research on your term, “money shifting” from your original post and that’s probably what is being prevented

Money shifting only happens in manuals, where you can downshift into a higher RPM than the engine would tolerate (e.g. if you’re in 5th gear at 7000RPM and instead of going to 6th you go to 4th, the engine would go way beyond its limiter), and the engine (and possibly transmission too) would break. Expensive shift…

So, yes, the auto is foolproof in that regard.
Do you think you may have been trying to downshift while the engine was already in high RPM? If so, that could be it, because the transmission will NOT obey any command to downshift until it’s in a range that’s acceptable (e.g. if you’re at 6k RPM and try to downshift it won’t do it, unless you slow the car down to 5k RPM, then it will).

[Axylus]

Originally Posted by M2siast

Money shifting only happens in manuals, where you can downshift into a higher RPM than the engine would tolerate (e.g. if you’re in 5th gear at 7000RPM and instead of going to 6th you go to 4th, the engine would go way beyond its limiter), and the engine (and possibly transmission too) would break. Expensive shift…

So, yes, the auto is foolproof in that regard.
Do you think you may have been trying to downshift while the engine was already in high RPM? If so, that could be it, because the transmission will NOT obey any command to downshift until it’s in a range that’s acceptable (e.g. if you’re at 6k RPM and try to downshift it won’t do it, unless you slow the car down to 5k RPM, then it will).

Hmm maybe I can try to explain what happened again.
I was driving ~35-40 mph. I stepped on the brake, but I wanted to get back up to speed so I immediately and normally stepped on the throttle. While I was gaining speed, the rpm increases to ~3k, the point at which I expected it to upshift, but the rpm stayed 3k and I pressed the throttle a little more and it increased past 3k and wouldn’t upshift. It finally shifted up or down (I don’t remember which) when I finally let off the throttle completely and let the engine brake itself

[M2siast]

Originally Posted by Axylus

Hmm maybe I can try to explain what happened again.
I was driving ~35-40 mph. I stepped on the brake, but I wanted to get back up to speed so I immediately and normally stepped on the throttle. While I was gaining speed, the rpm increases to ~3k, the point at which I expected it to upshift, but the rpm stayed 3k and I pressed the throttle a little more and it increased past 3k and wouldn’t upshift. It finally shifted up or down (I don’t remember which) when I finally let off the throttle completely and let the engine brake itself

Were you going uphill?

[Axylus]

Originally Posted by M2siast

Were you going uphill?

Downhill, but nothing extreme. Slight downward tilt

Downhill in both cases of the 3k and 6k rpm… seems downhill is the common factor of weirdness here

[M2siast]

Originally Posted by Axylus

Downhill, but nothing extreme. Slight downward tilt

Downhill in both cases of the 3k and 6k rpm… seems downhill is the common factor of weirdness here

Makes sense.
The car will hold the gear to engine brake.

[TheDrivenGarage]

Are you saying that when you left off the gas, it seemed to hang on the revs and not shift gears? If so, the trans is programmed to try and anticipate what you may be trying to do, I have had it get it wrong and stay in a lower gear at high rpm Instead of shifting to the next gear. It startled me a bit on an on-ramp as I was still in break in period and didn't want the revs to go too high.

It's happened to me once or twice since, where it seems to get its programming a little off. In those cases I just grab the paddles and shift to where I want it to go, and then let it go back to auto mode and its fine. I have never had it get confused in regular driving, just when driving a bt more sporty or coming off a sporty maneuver.

[Shadak]

Originally Posted by TheDrivenGarage

Are you saying that when you left off the gas, it seemed to hang on the revs and not shift gears? If so, the trans is programmed to try and anticipate what you may be trying to do, I have had it get it wrong and stay in a lower gear at high rpm Instead of shifting to the next gear. It startled me a bit on an on-ramp as I was still in break in period and didn't want the revs to go too high.

It's happened to me once or twice since, where it seems to get its programming a little off. In those cases I just grab the paddles and shift to where I want it to go, and then let it go back to auto mode and its fine. I have never had it get confused in regular driving, just when driving a bt more sporty or coming off a sporty maneuver.

this happens to me from time to time, i think it was always when braking a bit hardee before a round about, then leaving it, it would hold 2nd a bit more than id expect before shifting to 3rd, probably because it thought i wanted to be a bit sporty? Nothing crazy though, it shifted at around 4k instead of 2k iirc

[tylerdurdem]

Doesn't sound like anything is wrong, the shift logic has a ton of parameters like incline, load, brake application, speed obviously. If it hasn't chosen the gear you want, it has paddles . . .

[Ravenseal]

Buy a manual next time