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Discussion Starter #1
V6 owners I'm wondering what your typical shifting behavior is. Here is why I ask:

I've noticed on my '12 that when coasting typically between 25-40mph (40-65kph) and reapplying gas there is sometimes a short maybe half second/500 millisecond delay and then a noticeable engagement. It's not rough per se, but it's almost like a small slip and catch instead of being engaged the whole time while coasting. Then pulling right from the instant the gas is re-applied as opposed to a delay.

It feels more like a torque converter is slipping then re-engaging in a firmer action that is somewhat abrupt after a slight but noticeable delay and not the behavior of trying to figure out if it needs to stay in gear or downshift (but maybe not, perhaps I'm always in between gears and so it's not sure which?). This is why I need to crowd source and see what others experience. The transmission is usually very buttery, especially at highway speeds where it downshifts and upshifts effortlessly and very smoothly/confidently.

For background I'm not mashing the gas pedal at all, this is going between stop lights or being in traffic coasting in this speed range and then normally reapplying gas for 1-2 seconds before letting off again with ebb and flow. I just notice the transmission drop the rpms drop during the coast which is normal, then the gas pedal lightly, rpms come back up from 1,500rpm to say 2,200rpm which is normal, but at this instant there is a half second delay and subtle grab instead of an already engaged (and no delay or no grab) smooth pull forward.

Thoughts?
 

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The trans with my '11 V6 while coasting is engaged. While decelerating it will downshift according to road speed and usually is in a gear which is higher (lower numerical ratio) than when throttle is applied. Then when applying throttle the trans generally will downshift to a lower (higher numerical ratio) gear which includes a slight hesitation while the system determines into which gear the transmission needs to shift.
 

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I think what you may be feeling is torque converter locking/unlocking. When I exit the interstate, and coast down the off ramp, I can feel the engine braking in effect until I get down to a certain speed and the TC unlocks, which feels like a lurch forward. Although it feels like acceleration, it's actually just a decrease in deceleration. I've never had any other vehicle feel this way.
 

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Thanks for your reply JuneBug..My previous Toyota (Sienna) did the same thing when coasting say toward a stop sign &
I often wondered why it always seemed to jump out of gear..Now I know...My new RAV4 limited does the exact same
thing..The TC just unlocks about 6-8 mph...Knowledge is wonderful...Again, Thanks
 

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Discussion Starter #5
It's just a strange sensation I guess. Like it's slipping and then grabbing somewhat noticeably almost like a soft thud. You apply gas and it's "baahh-dah" with a hesitation and harder bump. Must be the torque converter.

Last night I was at the front of a traffic light next to someone waiting for it to turn green. There are two lanes that directly lead to a long tunnel onramp that's flat and then downhill slightly to the interstate. Before the tunnel starts it becomes one lane.

The light went green and I didn't mash the throttle because I didn't want that throw back in your seat torque steer, but I definitely applied the gas to get out front not really thinking twice about it. However instead of winding through first gear to get ahead of this older Mazda 3 next to me (which should have been casual and very easy) the Rav just dogged its way through 1st as I was all of a sudden caught off guard thinking "c'mon, reach your 2,500k rpm sweet spot and kick in already what's wrong with you". The Mazda 3 was apparently also trying to be first to the single lane to merge and was flooring it plus inching ahead of me. I couldn't believe it. This is actually dangerous and partly why I purchased the V6 so that if I needed power to dart in city driving to avoid situations like this I could.

At that point though I was already committed so I put my foot all the way to the floor to get it to do something before the lane ended. Right as I was cresting past 2k rpm and thinking "ok finally, it'll be fine despite the extreme lag" the damn thing down shifted to 2nd! What. The. F... What part of my-foot-is-to-the-floor does my transmission not understand? So bizarre. I've had this happen a few times while trying to merge onto highways as well.

It literally drove as if I had the 4 cylinder and was doing everything it could to get to 60mph in 10 seconds or longer.
 

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No such issues with our RAV4. Just aim, mash the gas, steer and you're gone. If driven that way (never with the wife anywhere in the vicinity) it would take a very fast car to outrun it. However if you take off at lesser pedal and then decide you need more acceleration it may actually feel slow. That happens when you've caught the transmission having just shifted into second (with low engine RPM and torque) but your going just barely too fast for it to downshift back into first but where it would've still been if you'd used full pedal initially.
This is easily tested with low speed roll-ons from various speeds followed by full throttle.
It's also why the 5-60mph tests of most cars I see in Car & Driver are slower than the 0-60mph times.
 
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No such issues with our RAV4. Just aim, mash the gas, steer and you're gone. If driven that way (never with the wife anywhere in the vicinity) it would take a very fast car to outrun it. .......
LOL ^^ I've own muscle cars & that is exactly what I call the wife's 2008 RAV4 Limited v6.

Last year she came home from work & was excited to tell me, a Honda Civic rice rocket was revving his 4 cyl. at a stop light & looking over.
- an excellent driver & she obviously couldn't resist (the seemly easy challenge
- quickly dusted him off, before he knew what hit him
- embarrassed young guy wouldn't even look back over again
Exactly why Toyota, never attempted to put a 2nd v6 emblem on the rear...a sleeper move !!
 

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Discussion Starter #8
No such issues with our RAV4. Just aim, mash the gas, steer and you're gone. If driven that way (never with the wife anywhere in the vicinity) it would take a very fast car to outrun it. However if you take off at lesser pedal and then decide you need more acceleration it may actually feel slow. That happens when you've caught the transmission having just shifted into second (with low engine RPM and torque) but your going just barely too fast for it to downshift back into first but where it would've still been if you'd used full pedal initially.
This is easily tested with low speed roll-ons from various speeds followed by full throttle.
It's also why the 5-60mph tests of most cars I see in Car & Driver are slower than the 0-60mph times.
I'm wondering if maybe it did somehow start off more in 2nd, this would definitely explain the serious reluctance to go. It felt like the longest gear ever slowly building when first usually takes off pretty snapily. The other factor I'm realizing is that the car had only been driven a couple of minutes at that point after being parked for hours and I wonder if the ECU was somehow limiting power as a way to protect cooler components before they had a chance to get to operating temperature.

But that also frustrates me, if you need your vehicle to do something you need it to do something, there can be no hesitation or the nanny system itself is only creating the accident not the actions it's trying to protect. The other day I turned off the VSC just to give it a try and that really did open the car up, it was moving pretty well enough to impress even me. And if you can't tell as an engineering student I am not that easy to impress.

As a side note my battery is leaking acid and corroding the positive battery terminal. So I took the terminal off to clean it and let it sit for a long while to reset the ECU. Wondering if this might help for future driving while the ECU remaps all the vectors and my inputs better.
 

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The other factor I'm realizing is that the car had only been driven a couple of minutes at that point after being parked for hours and I wonder if the ECU was somehow limiting power as a way to protect cooler components before they had a chance to get to operating temperature.
Temperature definitely is a factor but usually I only notice it in winter when cool is cold. If I make repeated attempts at spirited takeoffs when our V6 RAV4 has been sitting overnight, until the temps gauge moves off of C at least a little I know what an I4 must feel like. Just ordinary power. Actually thought something was wrong the first couple times it happened. Ahhh, but then it comes back alive and it's off like a shot again. >:D
 

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Okay, just ran some low speed acceleration tests (rate of speed was high) on the wife's RAV4 after changing a couple ignition coils.
Punching it from a stop (warmed up) gives the expected jackrabbit response. (And with 4WD there is no wheelspin or torque steer.) Rolling starts from 5, 10, 15 & 20mph give impressive acceleration as it downshifts to 1st and you're doing 40mph in what seems like half a second.

Between 20 & 25 it gets very interesting as around 22 is the limit to the 1st gear downshift. As I mentioned in my other post catching it just fast enough that is only goes to 2nd makes it feel pretty dead by comparison. That speed is 24mph near as I can tell. From 30+ it starts to feel strong again but the Achilles Heal is 24mph.

And yes, I did destroy the evidence, namely opened the back door and pushed all my wife's stuff back up against the rear seat. Somehow it was all stuffed against the door. :wink
 
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Discussion Starter #11
Solid work!

So if you get beyond 24mph then the Rav4 won't downshift back into 1st it will just wait and build rpms up until it reaches it's torque curve. Interesting.
 
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