Inconsistent Power in EV Mode

[First time hybrid owner]

I’ve had my 2013 Fusion Hybrid for over a month now and if I work really hard at it, I can average 46 mpg in mostly suburban driving. However, this is accomplished by “tricking the engine”, meaning I mostly accelerate using ICE and then take my foot off the gas and press it again lightly so it kicks into EV mode. Then every time the ICE kicks in, I will repeat that action so it will stay in EV mode as much as possible.

 

My frustration so far is that how hard the car allows me to accelerate while still in EV mode (meaning how hard I can push down on the gas pedal before the ICE kicks in) varies every minute or two. (I can tell because I am in Empower Mode, so there’s a blue bar showing EV mode).

 

Very occasionally while I’m driving, there is a large amount of blue showing in the display (going above the 2^nd line on the graph) so I can push hard on the gas pedal and stay in EV Mode. But often, there’s only a tiny amount of blue showing, so the ICE kicks in very quickly. Has anyone else experienced this or know why the amount of throttle allowed in EV mode is so inconsistent and what could be done about it?

 

Also, sometimes when the ICE is on, it will stay on for a few minutes while I’m driving, even though it normally immediately kicks in to EV mode when I take my foot off the gas pedal. This completely eats into my mpg. Again, I don’t understand why it’s doing this or if anything can be done about it.

 

Any feedback is appreciated!

Thanks,
Jeff

Edited August 31, 2013 by First time hybrid owner

[corncobs]

Welcome to the forum Jeff.

 

What you expirencing and describing is very normal behavior and largely depending on SOC and road conditions ( flat, up or downhill ).

 

With each second you are accelerating the HVB is charged and I believe the harder you do that the faster the SOC goes up and you see a higher threshold in the Empower screen.

 

I actually do the same thing as you in terms on P&G and the only thing that's different is that I rarely see a full EV frame up to the second mark. Sometimes I keep the ICE running intentionally with a low throttle position to get my SOC up while the inst. MPG shows around 30 MPG. Usually only works on a flat stretch of road while staying within the first line with the white bar for ICE power.

 

Last but not least what you are saying about the ICE stays running is probably when you first start into your drive correct?

Do you already have the PCM update for your car applied? The warm up behavior is slightly different between before and after PCM update.

[murphy]

The pulse and glide technique has always been to accelerate to your desired speed using the ice and then blip the throttle to switch to EV mode. The ICE will stay on if the sensors aren't up to operating temperature. The lower the SOC of the HVB is the harder it will be to stay in EV mode. At the SOC lower trip point there is no choice, the ICE is going to start unless you are going down a steep hill that can charge the HVB. The power drain of the A/C will figure into when the ICE will start.

[TX NRG]

Agree with all the comments above. The shaded blue EV acceleration threshold in Empower is proportional to the State Of Charge of the High Voltage Battery. The higher the charge, the larger the EV acceleration window is. The chevron above or below the battery indicates charging or discharging of the HVB at that moment.

[First time hybrid owner]

Hi everyone,

Thanks for your feedback.

 

Honestly, I'm not sure the battery level has much to do with how much EV power the car gives me. Half the time, the battery is at least half charged when there's either barely any EV power available or no EV power at all. And the weird thing is that most of the time that I get at least 2 bars worth of EV power is when I'm on my way home, a few blocks from home, and suddenly the available EV power goes way, way up -- regardless of how charged the battery is.

 

I understand the need for the engine to warm up, but the strange thing is that it's at least 70 degrees here in PA and it usually starts out in EV mode. But then as soon as the ICE kicks on, the engine then stays in ICE mode for a long period of time. And this seems to be happening more and more frequently. The first few weeks I had the car, it happened much less often.

 

And the AC is off just about every time this is happening.

 

I haven't gotten the update yet -- in fact, we haven't even gotten anything from Ford about getting it. Can anyone tell me how that works -- do I need some kind of paperwork to take in that shows it should be done? Does it need to be done at a Ford dealer?

Thanks!

[corncobs]

When driving home have you noticed a "+" sign next to EV? That would explain the sudden higher EV availibility and is a feature that allows for more HVB drainage when the FFH is getting close to a frequent location.

 

The ICE doesn't care about the outside temp. Even after baking a full day in the sun at 100* the ICE will run when leaving after work just as you describe it. It will actually run longer without the PCM update.

 

You should get a letter at some point but its not needed to get it applied. Just tell you dealer about the upgrade there is a number that I can't remember right now (13B07 or something like this). There are a couple threads on the topic and important is that the dealer uses the correct version of the computer system to update the PCM which can also be found here on the forum.

[hybridbear]

Hi everyone,

Thanks for your feedback.

 

Honestly, I'm not sure the battery level has much to do with how much EV power the car gives me. Half the time, the battery is at least half charged when there's either barely any EV power available or no EV power at all. And the weird thing is that most of the time that I get at least 2 bars worth of EV power is when I'm on my way home, a few blocks from home, and suddenly the available EV power goes way, way up -- regardless of how charged the battery is.

 

I understand the need for the engine to warm up, but the strange thing is that it's at least 70 degrees here in PA and it usually starts out in EV mode. But then as soon as the ICE kicks on, the engine then stays in ICE mode for a long period of time. And this seems to be happening more and more frequently. The first few weeks I had the car, it happened much less often.

 

And the AC is off just about every time this is happening.

 

I haven't gotten the update yet -- in fact, we haven't even gotten anything from Ford about getting it. Can anyone tell me how that works -- do I need some kind of paperwork to take in that shows it should be done? Does it need to be done at a Ford dealer?

Thanks!

Air conditioning will suck a lot of amperage from the HVB and will make the ICE run more often. Air conditioning use seems to make the threshhold go down for when the ICE kicks on and how hard you can accelerate in EV. You're getting great mileage so far for a first time hybrid owned but with time I'm sure you'll do even better. Check out this thread if you haven't already. It has links to some topics about maximizing fuel economy. With the way Ford programmed their software it's harder to just get in and drive and get great MPGs, however, once you understand a bit about how the software is designed to function and some of the science behind the car you'll be able to control the car better than the computer can and your mileage will go even higher. You don't actually want to accelerate in EV unless you aren't going very fast. It's better to accelerate using the ICE and then use EV for maintaining your speed on level ground. One of the topics mentioned in the Welcome thread linked above has a more detailed explanation about that.

[majorleeslow]

DW/oB and DWL works for me. I avoid full stops as much as possible. keeping the momentum steady thought the trip. Regen is practically useless. Ive had brake scores in 70's with high mpg just due to above. ( not saying that you don't need to regen for high numbers, you do just pointing the fact that brakes are enemy of mpg.)

 

After the tsb13b07 I'm doing above 55 mpg very consistent in city trips. following a big vehicle also helps a lot in mpg. even an suv or a minivan. Climate ctrl and rain reduces mine by 3-6 mpgs from similar trips in dry weather. I'm still logging each trip with all electrical loads (fan ac radio defrost etc) will inform more as I find out. So far fan vs no fan has the least impact on mpg (matter of fact with fan average is better than with no electric loads) fan with radio and just radio are chronologically lower. The cabin fan may be doubling up as battery fan or reducing drag somehow depending on its intake/exhaust. AC and more passenger wt drops the number further from previous variables. hills and shorter then 15 miles also don't give good mpg. 30+ mile city trips yielded the best mpg for me.

Edited September 7, 2013 by majorleeslow