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Discussion Starter #1
I've had my Mo for a couple of months now and I love it. One thing I have noticed however is sometimes when I am coming to a stop with my foot on the brake, I feel a very slight surge of power and I have to brake a little harder to get the Mo to stop smoothly. It is not a smooth even brake. The surge is sometimes a little scary. Has anyone else experienced this or have any explanation for whether this is normal or not?
 

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Yes Ella, it's the torque converter unlocking. I had the same feeling when new. I am used to it now. You'll anticipate it and learn to expect it as usual.
 

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I don't mind it at all, except when I am in traffic doing 20 mph. The convertor keeps locking and unlocking a thousand times which becomes annoying really fast....:D
 

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Discussion Starter #4
I guess I haven't driven the Mo long enough to actually notice a pattern. Does this mean it only happen when I am driving slow because I dont notice it all the time I just havent actually paid attention to a pattern of when it happens.
 

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It happens to me, but I find myself hitting both the gas and the brake. I wish they were a little farther apart.
 

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ella138 said:
I guess I haven't driven the Mo long enough to actually notice a pattern. Does this mean it only happen when I am driving slow because I dont notice it all the time I just havent actually paid attention to a pattern of when it happens.
The lock - unlock happens at 18 mph, or very close to that.
 

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zebelkan - if traffic requires driving for extended periods at low speeds (20 mph) put CVT in Ds to bring the revs up a little...will be a lot smoother and better for the entire powertrain as well...
 

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senza said:
zebelkan - if traffic requires driving for extended periods at low speeds (20 mph) put CVT in Ds to bring the revs up a little...will be a lot smoother and better for the entire powertrain as well...
Good tip, and it makes sense. I will do that. Thanks....:29:
 

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Discussion Starter #10
What does put the CTV into Ds mean???
 

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ella138 said:
I've had my Mo for a couple of months now and I love it. One thing I have noticed however is sometimes when I am coming to a stop with my foot on the brake, I feel a very slight surge of power and I have to brake a little harder to get the Mo to stop smoothly. It is not a smooth even brake. The surge is sometimes a little scary. Has anyone else experienced this or have any explanation for whether this is normal or not?
Just wanted to combine some of these answers and put them into pain English in case people haven't figured out the "locking and unlocking of the torque converter" thing.

As you're braking, the engine is still engaged, and the RPMs might jump up a bit to help you brake. It's essentially "engine braking" in a manual transmission, where you shift it into a lower gear to make the engine slow you down so you don't have to brake as hard. The MO does this automatically, and they call it "downhill assist" or something like that.

Anyway, as you're coming to a stop, the engine is helping you to brake (by keeping the torque converter "locked"). But once you get down to a particular speed (about 18mph) the engine decides that it's time to release it's grip and go to idle. This is the "unlocking" of the torque converter, and that's when you feel the surge of power.

So it's not really a surge of power, but the engine releasing its grip, therefore releasing some of the braking power.

It's caught me by surprise a couple of times as well, but it's normal behavior and once you know about it you do get used to it. Doesn't bother me anymore.
 

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ella138 said:
What does put the CTV into Ds mean???
You have an SE model which doesn't have the Ds mode for the CVT. Rather you have the sequential shift function. My 03 SE has D, Ds, and L.
 

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Glad somebody brought this out... thought I have a gremlin in my MO. I was on a traffic light stop... as soon as I took my foot off the brake pedal, before I can even press the gas pedal there was a surge of power and MO took off. Good thing that I always make a habit to keep a good distance otherwise I could have rear-ended somebody. It's scary though.

I found myself talking to my MO (like a horse......Hooooo...Hoooo. slow down). Too much horsepower there.
 

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Sounds like we have a bunch of manual tramission drivers here. I know I was one of them.
 

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chita1987usa said:
before I can even press the gas pedal there was a surge of power and MO took off.
I often take off from lights, but yesterday I almost paid the price. Someone too old to drive took a really late red coming off the Route 95 exit ramp, and I had already gotten underway from my green. I had to brake a lot harder than I expected to avoid T-boning this guy, and it felt like the Mo just wouldn't let up. I figure after 47,000 miles, Nancy knows how I like to leave freshly green lights.

If nothing I practically sent him into cardiac arrest, so it wasn't all for naught :) Hopefully he won't do that anymore.

(oh, and yes, 3 of my 6 cars were sticks)
 

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Discussion Starter #16
Just wanted to combine some of these answers and put them into pain English in case people haven't figured out the "locking and unlocking of the torque converter" thing.


Thanks for that explanation. It is excellent and now I understand. It's refreshing when someone can talk in plain English to us technically challenged people.
 

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I have just recently started noticing the TC unlocking in my new MO too. I got stuck in traffic on the freeway going 20mph and it felt anything but smooth as the TC thumped into lock and out again repeatedly. I've never noticed this so much in other auto tranny cars I've owned- I guess its the engine braking "feature" combined with the really low rpm that the TC locks up at. I actually wish they had made it more like a normal auto this way; it really takes away from the otherwise smooth performance, esp. in traffic.:headshake
 

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Go by the dealers and try a few of the new cars.
You may have a problem.
I certainly have not ever noticed the TC locking/unlocking continually.
I think it IS the same as other auto trannys on this issue.

Homer
 

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hfelknor said:
Go by the dealers and try a few of the new cars.
You may have a problem.
I certainly have not ever noticed the TC locking/unlocking continually.
I think it IS the same as other auto trannys on this issue.

Homer
I'm glad you said that Homer. My MO also stops very smooth. I've noticed no TC locking issues. I sit in alot of traffic.:(
 

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hfelknor said:
Go by the dealers and try a few of the new cars.
You may have a problem.
I certainly have not ever noticed the TC locking/unlocking continually.
I think it IS the same as other auto trannys on this issue.

Homer
Homer,

This behavior is normal. If you drive continuously at or around 20mph as in rush hour traffic, as your speed goes over and falls below the 18 or 20 mph the TC will lock and unlock and you will notice it. This behavior is not noticable in a normal automatic transmission because the TC is designed to lock up (if it has the feature) at high speeds, usually around 50 to 60mph and past the last gear of your transmission, and only when engine does not experience excessive load. Try it with your other car. Speed up to say 50 mph and very let loose on the gas pedal but still accelerate veeeery slowly while watching the engine rpm. You will notice a small drop in rpm at somepoint. That is when TC locks up. Its purpose is to improve gas mileage.
 
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