EV Now, Downhill, Engine High Rev

[eminaise]

Hello, 

I'm a newish focus energi owner that lives on top of a hill in Washington State.  I start my commute fully charged and descend about 700 feet in 4 miles on EV Now mode.

Near the bottom of the hill, the motor starts and revs really, really high (like as high as it can rev).  Is this normal?   Why is it using gas when the battery is fully charged and I'm going downhill?

-Matt

Seattle, WA

[jdbob]

I have the same problem. It's about 600 feet drop down into town (about 4 miles away) from my house. I set the touchscreen to the page that shows battery percentage before I leave. There is an uphill near the beginning of my trip before descending. It will fall below 100% once I get to the top any time of the year, at that point I switch from D to L. In winter (because of the heater power draw) It normally doesn't rise back up to 100 by the time I get to the bottom of the hill so no problems. But in summer once it gets back up to 100% I switch back to D until I can burn off some power in town.

 

The way Ford intended it to work is to apply engine braking without spark or gas rather than just use the friction brake. Personally I think this is pretty stupid, they should at least have a setting to disable that. But since I don't use the engine for months at a time if the engine starts it actually runs the engine until it heats up. 

[murphy]

With the battery full regenerative braking is not possible.  The ICE is operated like an air compressor to provide the back pressure to prevent the car from needing heavy braking in a downhill situation.  No gas is being burned.  It is a fuel injected engine so in this mode the injectors are turned off.

[eminaise]

Thanks!! 

[jsamp]

If you wanted to capture the electricity from your 700' downhill, you need to start with your battery below 100%.  If you started at 80-90% or so, it would most likely max it out by the bottom of the hill. 

 

Like Murphy said you are not wasting any gas when the "engine brake" goes on, but you are not capturing any electricity either.  You paid for it on your way home going up the hill, might as well get some of that back if you can.

 

 

"focus energi"?  You mean fusion right?

Edited June 27, 2018 at 04:06 AM by jsamp

[Paul Creed III]

I had this super high rev happen this morning.

 

Started with 100% HVB charge in Auto Mode, HVAC completely off, along with recent ICE usage and fresh gas, 65F temps, and the ICE kicked on in my driveway at a couple MPH. The ICE ran, along with some HVB usage, for a mile or so through two stop signs/red lights. When I went to slow down (from ~20 MPH) at the third red light, the ICE was still running and kicked into super high rev even though the downgrade was incredibly tiny coming up to the light. 

[jdbob]

If you wanted to capture the electricity from your 700' downhill, you need to start with your battery below 100%.  If you started at 80-90% or so, it would most likely max it out by the bottom of the hill. 

 

It would have nice if Ford had added an option to set the maximum charge percentage just for such situations, but they didn't, so you can't start at 80-90% without some annoying manual unplugging.

[Russael]

I had this super high rev happen this morning.

 

Started with 100% HVB charge in Auto Mode, HVAC completely off, along with recent ICE usage and fresh gas, 65F temps, and the ICE kicked on in my driveway at a couple MPH. The ICE ran, along with some HVB usage, for a mile or so through two stop signs/red lights. When I went to slow down (from ~20 MPH) at the third red light, the ICE was still running and kicked into super high rev even though the downgrade was incredibly tiny coming up to the light. 

 

Guessing you were driving in L.

 

Drive in D until you expend maybe a mile of charge, then switch back or the ICE will kick on as soon as you lift your foot off of the accelerator.

[Davidoo]

I've had this happen several times in mountains.  I'm going downhill in L and eventually the HVB gets to 100%.  After that, need to take it out of L to stop the engine high revving since the battery is at 100% and it can't charge it anymore.  I had always assumed this is normal behavior.  Hopefully no damage occurs as it does seem the engine races very, very high.

[Paul Creed III]

Guessing you were driving in L.

 

Drive in D until you expend maybe a mile of charge, then switch back or the ICE will kick on as soon as you lift your foot off of the accelerator.

 

Yup, it was in L yesterday. Did the very same drive today just in D, with the HVAC on a touch, and the ICE didn't start at all. I'll keep it in D for an initial short distance to "burn off" some charge then switch to L for my city driving. 

 

Thanks!