Interesting Observation with Nissan CVT / DFCO

[Miller88]

I had a rental Nissan with a CVT this weekend. I was a bit nervous at first, because the car had 50K miles. The CVT was definitely living on borrowed time.

They seem to be quite agressive with DFCO. Whereas other vehicles (manual and automatics) seem to let go of DFCO at a certain point - RPM/Speed, the Nissan was able to hold onto it until 10 or 15 MPH when slowing down. At which point it would unlock the torque converter and start using fuel again.

The other interesting thing I noticed was - it is possible to acellerate (slightly) downhill while still maintaining DFCO. My Focus won't hold itself back on moderate-large hills, so it's not always an issue, but on small hills I can either coast in neutral with the engine running ... or leave it in gear and lose some speed while it is in DFCO.

It appears if you are going down a hill you can give the car a small amount of throttle, and it will open the throttle without getting out of DFCO. Pretty interesting!

I ended up getting ~30MPG on the tank where I drove from PA to NYC ... including about 2 hours of driving around Manhattan. Don't think you can get more "city" driving than Manhattan (specifically times square) at 530 on a Saturday night!

Anyone else notice this with the Nissan CVTs?

[MetroMPG]

What model Nissan was that?

Originally Posted by Miller88

The other interesting thing I noticed was - it is possible to acellerate (slightly) downhill while still maintaining DFCO.

Assuming you were seeing DFCO on an aftermarket gauge (?) you would also have to wonder whether you were seeing "real" DFCO vs. the gauge's software interpretation of when it might be happening.

I've spent precious little time driving CVT's. A bit of time in a Jeep Compass and Audi A4 (where I learned I could "short shift" them) and half an hour comparing a 2014 Mirage CVT vs. the 5-speed.

[Miller88]

Originally Posted by MetroMPG

What model Nissan was that?



Assuming you were seeing DFCO on an aftermarket gauge (?) you would also have to wonder whether you were seeing "real" DFCO vs. the gauge's software interpretation of when it might be happening.

I've spent precious little time driving CVT's. A bit of time in a Jeep Compass and Audi A4 (where I learned I could "short shift" them) and half an hour comparing a 2014 Mirage CVT vs. the 5-speed.

It was a 2012 Nissan Sentra. The Torque app (bluetooth adapter) was going to 99.9 - that's what lead me to believe it was doing a DFCO. On screen was displaying 60MPG when it would DFCO.

This seemed to idle up to speed if I used very little throttle. The torque converter would lock at 5 or 6 MPH.

[oldtamiyaphile]

Originally Posted by Miller88

It appears if you are going down a hill you can give the car a small amount of throttle, and it will open the throttle without getting out of DFCO. Pretty interesting!

I'd say more likely the pedal just has a bit of dead band.

Unless you compare to a manual version you can't say this DFCO tuning is CVT specific.

My Fiat will DFCO right down to ~900rpm with a manual trans.