Driven 2 FFHs, both behave differently, which one works correctly?

[Bobo]

I bought a 2014 FFH S on Carvana a couple of weeks ago. I drove the car for the trial period and liked it so much I returned it and bought a 2015 FFH SE instead.

I like it, but it seems to drive differently that the 2014, and I'm concerned.

The main difference is how high the engine revs when accelerating from a dead stop. In the 2014, when the ICE kicked in, it would drive the car at a lower rpm, unless I really dug into the pedal, then it would do it's typical CVT rev thing, and find it's 'ratio' or whatever.

The newer 2015 does the same thing, but not always. Sometimes, when I'm starting out from a dead stop, when the ICE comes on, it revs MUCH higher. Even if I'm NOT digging into the gas pedal. Today, for the first time, I heard it do both. It started in very low rpm, which was fine because I was really light on the pedal at the time. Then, out of the blue, it revved up to a higher rpm and stayed there. Almost as if it had downshifted! It did this with no change on the pedal pressure from me.

In short, it seems to be 'slipping out of gear'. I mean, I know it doesn't HAVE any 'gears', but that's the only way I can describe it. But I know that this is how a person might also describe normal operating behavior of a CVT too, which is frustrating! lol!

Maybe a better way would be to say, this CVT sometimes SOUNDS like I'm really digging into the gas pedal when I'm not. The other FFH that I drove for a week, never did this that I noticed. If I stayed out of the gas pedal and drove it gingerly, it would never rev like this.

Is there anything that would make a 2014 drive any differently than a 2015? Has anyone had or reported this kind of behavior? And what seems more like normal behavior? The higher revving at low speeds or the lower rpms at low speeds? I preferred the 2014 that kept at a low rpm until I asked for more. I'm hoping someone can shed some light before Tuesday, which is the last day I have to return this car to Carvana.

Edited April 7, 2018 by Bobo

[murphy]

There is no connection, or correlation, between the accelerator pedal and the engine rpm. The accelerator pedal is two variable resistors that are fed to the computer over 6 wires. All it does is tell the computer the position of the pedal. The computer controls the engine and tries to keep it at its optimum operating point. There is also no correlation between rpm and vehicle speed. Watch the charge level of the HVB when this happens. I'm thinking the charge level has reached its low point and the computer is increasing the rpm to recharge the battery. The computer can increase the rpm to charge the battery without having any effect on vehicle speed. You have to unlearn everything you know about engine sounds. Unlike a standard engine, which uses the Otto cycle, this engine uses the Atkinson cycle.

[md13ffhguy]

I had a 13, now an 18, and my wife has a 14. There are subtle differences in how each has felt to me. On the other hand, my wife probably wouldn't notice any differences. Although I believe the mechanics are essentially the same among them, I do believe there are some software differences between them that affect the transition between ICE and EV operation. The 18 also has an Eco button, which affects how often regen kicks in. I like it engaged, but I can see where others might hate it.

[Bobo]

Thanks. Drove it again today. I think I'm overthinking it. It did rev higher a couple of times today, but I just backed off the pedal a little and it settled back down.

I think there might just be a slight difference in vibration feedback from the 2014 to the 2015. The 2014 didn't seem to vibrate as much.
With our older Focus, I had to service the motor mounts at 70k and they were already needing another replacement at 110k.

I'm keeping it. It's got 15k/2yrs left on the factory powertrain warranty and longer on the battery.

Personally, I'm really digging the CVT for calm city driving.

Edited April 9, 2018 by Bobo

[ethermion]

Congratulations on your decision!

 

Our 2013 FFH is the lovely wife's car, and it is hands down the best car we ever bought. Forget mpg as you will enjoy not filling up so often. My wife's commute is 1 1/2 hours each way in seriously heavy/slow traffic. Instead of filling a 17 gallon tank every 4 days (she couldn't make a full week), she can go 2 weeks on the 13 gallon tank and still have gas left over. If I am an attentive husband and borrow her car for weekend errands - filling her up on the ride home, she might go months without hitting a gas station.

 

Dunno 'bout the 2014s and 2015s, but also be mindful that when the ICE is off, you hear things you would not otherwise. Going from EV mode to engaging the ICE will likewise be unfamiliar to your ears. Stomping the gas, well, it is a hybrid - you shouldn't be doing that often.

 

Be mindful that the ICE will kick on if you ask for heat on a cold engine. Asking for A/C on a low battery will likewise kick on the ICE. There are little things you can learn to make your ride like a sailboat on a sunny day. Perhaps not the fastest, but still good clean fun.

 

We got one of the earliest builds, and had a few teething problems, but warranty fixed everything. Close to 80k miles, and it still runs like new. Delightful.

[mwr]

Any number of things can determine when and how much the ICE kicks in, and I don't claim to have figured it all out. HV battery charge level is a prime one, though. I love it when the car accelerates quickly using the ICE and also EV, since the ICE sound is very low. Sometimes it accelerates that way, but some times it doesn't and the ICE is then much louder. Relax and enjoy it :-)

Edited April 10, 2018 by mwr