clunk noise - cvt

[tomrad]

Probably a normal thing, just noticed it tonight when I was just about to stop, had to take off again and sounded like a little clunk from the trans. Did it again at the next stop sign then didn't do it again. Anyone experience this? Kind of like a clunk because I didn't come to a complete stop before taking off again.

[MetroMPG]

Just a guess, but it sounds like maybe it's just going into neutral (Idle Neutral Logic) as you're stopping, but when you hit the gas and take off again it shifts back into drive.

Thread: CVT owners... what is "Idle Neutral Logic"? And what is it like to drive?

[Ares]

I have to agree with Metro. The mirage isn't quite as refined as it's supposed to be, but it works.

[R01k]

I've heard it too coming from my CVT. It's normal.

[cookiemonster]

Same here. Sometimes there is a bump from stop, I figured it was transmission engaging from neutral.

I wonder if there is the potential for future software/firmware updates from Mitsubishi to smooth out the transmission.

[IchabodCrane]

The CVT has an engine braking mode. When we brake, the trans stays somewhat engaged which causes drag on the driveline to help us stop.
When we decide not to stop but gas it again instead, the driveline load instantly reverses. (Like switching from push to pull)
This causes lash tolerance in driveline to "catch up" and gives us a little jolt due to the shock load.
This, combined with the computer trying to guess where to put the belt for the new input creates a bit of a rough restart.
Same thing happens with my ATV, it's a characteristic of engine brake capable CVT's

[Ares]

The CVT has an engine braking mode. When we brake, the trans stays somewhat engaged which causes drag on the driveline to help us stop.

I think another reason why the tranny does that is to save fuel. IIRC, there is a fuel cutoff mechanism that activates when the car is in gear (CVT/5spd) and no accelerator is applied.

Which is why one has to gauge whether or not to neutral coast or coast in gear.

[IchabodCrane]

I think another reason why the tranny does that is to save fuel. IIRC, there is a fuel cutoff mechanism that activates when the car is in gear (CVT/5spd) and no accelerator is applied.

Which is why one has to gauge whether or not to neutral coast or coast in gear.

IMHO engine braking fights against fuel saving as it eliminates coasting. Whether there be fuel cutoff or not, if it doesn't coast there are no free miles.

[debburyl]

Mine does the same thing. But noticed that if I slowly give it gas it don't do that as much.so if you give gas faster that's when you notice the clunk.

[tomrad]

Mine does the same thing. But noticed that if I slowly give it gas it don't do that as much.so if you give gas faster that's when you notice the clunk.

Yes, that's what I did, took off faster than usual. Has not made the noise since.
Thanks to all for the replies.