Question about Vios A/T

**PATSYS50** · October 22nd, 2010 10:25 PM

I have this observation between my Alterra and Vios, both automatic transmission.

After I reach e.g. 70 km/hr speed and let go of the gas:

For Alterra, the rpm goes down right away to minimum which is around 650. I expect this outcome as it is kina like the equivalent of shifting to neutral for manual transmission.

For Vios, the rpm stays where it was when I reached the 70 km/hr (about 2500 rmp, and very slowly go down until I come to a full stop. It only gets to about 650 rpm when I am totally idling.

Which one of the above is normal for an automatic transmission?

**anonemus** · October 23rd, 2010 08:56 AM

First, which response do you prefer?

**CivicVTi** · October 23rd, 2010 10:35 AM

Originally Posted by PATSYS50

I have this observation between my Alterra and Vios, both automatic transmission.

After I reach e.g. 70 km/hr speed and let go of the gas:

For Alterra, the rpm goes down right away to minimum which is around 650. I expect this outcome as it is kina like the equivalent of shifting to neutral for manual transmission.

For Vios, the rpm stays where it was when I reached the 70 km/hr (about 2500 rmp, and very slowly go down until I come to a full stop. It only gets to about 650 rpm when I am totally idling.

Which one of the above is normal for an automatic transmission?

For me, I think the behavior of the Vios is more normal since you are just letting go of the gas pedal and not actually shifting the transmission to [N]eutral while decelerating. Engine braking and downshifting is taking effect.

**krinkx** · October 23rd, 2010 10:01 PM

i notice this also with my civic and strada, both automatic... for the civic when going downhill, the rpm actually goes up but the strada remains near or equal the idle rpm...

the way i understand it, it is the torque of the engine... at minimum idle, the torquier engine can pull the car at a lower rpm than a less torquier one...

i am not sure though...

**niky** · October 24th, 2010 03:10 PM

It really depends on the gearing and the torque converter lockup point.

With the trucks, at 70 km/h, you're only doing 2000 rpm or under, so the torque converter doesn't lock-up, and the engine will go back to idle. With the Vios, you're doing slightly over 2000 rpm, and the torque converter stays locked up.