Engine runs when it doesn't need to.

[vidwiz]

Can someone please tell me why the powerboost does this:

I'm coasting downhill for several thousand vertical feet. The engine is off and the hybrid battery is accumulating a charge. When it gets to the maximum the algorithm will allow, which is about 70%, (I monitor the state of charge and amperage using the Torque Pro App) the engine comes back on and stays on. The engine will turn off if I slow most of the way down or stop, but then when it hits 70 again, engine is back on.

Just bugs me that I'm idling when there is seemingly no need for it. And with the engine idling while coasting down a hill at highway speeds, the mpg gauge reads only perhaps 22 which in itself seems really low.

Sponsored

 

[tbinmd]

Once the battery hits the full charge the engine is going to come back on for engine braking, rather than using regen. You could try using the brakes and slowing the truck down that way.

 

[thebigdu]

The PB starts the ICE for engine braking after the hybrid battery has reached a full charge. No fuel is going into the engine... It's rotating from the truck's momentum, and the engine's internal pressure is effectively slowing the truck down. If you pull up the Power Flow screen, it will tell you ICE is on due to engine braking. This helps save your friction brakes, same as in any non-hybrid vehicle.

 

[vidwiz]

Ok great answers, thanks. But why the low mpg reading then? This is the instantaneous/current mpg, not cumulative.

 

[Gros Ventre]

Alternatively you could put it in neutral and/or turn off the cruise control... Neutral is not a good idea and illegal in some states. In my observation the engine braking only kicks in if there is a speed set in the speed control and the system is well above the setpoint

 

[vidwiz]

Thanks, yeah all of this is no cruise control, I'm braking as needed.

 

[Gros Ventre]

Something I've noticed is use of the "double tap." On my Escape Hybrid there are times when you can get the engine to cycle off by giving the brake pedal a light "double tap." the engine then cycles off. The PB Seems to do that as well.

 

[EricR]

Ok great answers, thanks. But why the low mpg reading then? This is the instantaneous/current mpg, not cumulative.

This is different then my '21 PB. Just came down from McCall, ID (5,000FT) yesterday and on the downhills if the engine was "running" the instantaneous MPG gauge was pegged all the way to the right (maximum).

 

[Samson16]

This is different then my '21 PB. Just came down from McCall, ID (5,000FT) yesterday and on the downhills if the engine was "running" the instantaneous MPG gauge was pegged all the way to the right (maximum).

That seems to match what I'm able to simulate by coasting on slight downhills with my foot off the gas. Minimal regen of course but the instantaneous bar graph with your overall mpg avg superimposed above it shows pegged to the right before it disappears as the ICE shuts down for a spell.

 

[Oxford_Powerboost]

Ok great answers, thanks. But why the low mpg reading then? This is the instantaneous/current mpg, not cumulative.

Verify next time that you’re noticing this condition at the same time as the engine popping on while braking. That shouldn’t occur.
As I said above - it will at times choose to charge instead of cut fuel, but not when engine braking since it’s already fully charged.

 

[rtf150]

I tried multiple times today in my travels to recreate your scenario and I could not get the ICE to kick on. I was able to top out at the bottom of one of my downhills at 79 MPH. No engine break so I was unable to check MPG. Do you have a pic? Not much help I know but trying. I have read that the system will engage the ICE as an engine break and no fuel is being used as previously stated by @tbinmd and I have experienced the engine break scenario but never checked MPG.

 

[thebigdu]

I tried multiple times today in my travels to recreate your scenario and I could not get the ICE to kick on. I was able to top out at the bottom of one of my downhills at 79 MPH. No engine break so I was unable to check MPG. Do you have a pic? Not much help I know but trying. I have read that the system will engage the ICE as an engine break and no fuel is being used as previously stated by @tbinmd and I have experienced the engine break scenario but never checked MPG.

Were you braking here or just coasting? And are you sure your HV battery was at max charge? The EV Coach screen is the best indicator you can get; once the HV battery has been topped off, the Charging bar will get very short.

Apologies if you already know all of this, in case I sound pedantic.

 

[rtf150]

Were you braking here or just coasting? And are you sure your HV battery was at max charge? The EV Coach screen is the best indicator you can get; once the HV battery has been topped off, the Charging bar will get very short.

Apologies if you already know all of this, in case I sound pedantic.

100% coast. Very little brake. I am not sure about charge of the battery. I have watched the EV coach previously and will try again. I had another down hill today but used it for a different situation…pushed her to 101. Couldn’t resist.

No apologies needed and thanks for improving my vernacular!. Pedantic…

I’ll keep trying as in my travels I encounter many opportunities to coast. THANKS!!!

 

[thebigdu]

100% coast. Very little brake. I am not sure about charge of the battery. I have watched the EV coach previously and will try again. I had another down hill today but used it for a different situation…pushed her to 101. Couldn’t resist.

No apologies needed and thanks for improving my vernacular!. Pedantic…

I’ll keep trying as in my travels I encounter many opportunities to coast. THANKS!!!

Happy to help!

Someone can correct me if I'm wrong, but I think engine braking only kicks in when you're applying the brake. Otherwise I'd imagine the truck will just let you coast in EV mode for as long as you'd like or up until the HV battery is depleted from electronic draw.

Sponsored