Fuel Efficency of the ICE

[Nmadole]

When your FFH is running on ICE only at approx 55 MPH what instant MPG are you seeing... My ICE only runs at about 18-20 MPG at 55MPH

[ptjones]

The ICE MPG is consently changing do to the battery charge level. In a few minutes it will be up to 35-40mpg as it charges the battery up.

[acdii]

Nope, sorry not in our cars. With a near full pack, its still only around 30 MPG. Compared to the 2010, it is way below where is should be on the scale. When backing off the throttle and before it kicks to EV, the bar should be going up, but it doesnt, it kicks right into EV, and as soon as you give it a touch to maintain the speed, it kicks back to ICE, and back to 30 MPG or less. Not sure what it is yet, but something is holding the car back, either the tires, or something in the driveline thats causing excessive drag. When I take my foot off, it slows down quickly, and the upper arrow above the battery is not lit up. I have a lot of pics I took of the dash readout in my 2010, to prove I know how to drive a Hybrid, the new one really is no different than the other ones, only that the pack is Lion and not NImH, and it can be EV at 62 instead of 45, but the same driving techniques apply to it, but it likes longer braking than the older ones.

[terryb]

Nope, sorry not in our cars. With a near full pack, its still only around 30 MPG. Compared to the 2010, it is way below where is should be on the scale. When backing off the throttle and before it kicks to EV, the bar should be going up, but it doesnt, it kicks right into EV, and as soon as you give it a touch to maintain the speed, it kicks back to ICE, and back to 30 MPG or less. Not sure what it is yet, but something is holding the car back, either the tires, or something in the driveline thats causing excessive drag. When I take my foot off, it slows down quickly, and the upper arrow above the battery is not lit up. I have a lot of pics I took of the dash readout in my 2010, to prove I know how to drive a Hybrid, the new one really is no different than the other ones, only that the pack is Lion and not NImH, and it can be EV at 62 instead of 45, but the same driving techniques apply to it, but it likes longer braking than the older ones.

 

Have you tried feeling for hot wheels indicating brake drag right after completing a drive segment.

You do have symptoms of mechanical drag/losses.

 

TerryB

 

 

[acdii]

Yep, and found nothing. I did notice there is a draw on the traction battery while in park with everything off except ignition. The discharge arrow was showing, which seems a bit odd.

[DeeCee]

Checked mine today at 55 mph. On ICE the instant mpg display ranged between 20 and 40 on level to slight uphill. As soon as I started downhill the system would go to EV mode. I was running at 55 mph with the ACC engaged. On uphill climbs it would drop to 20 mpg or slightly below. Outside temp today was about 50 deg. Lifetime mpg reading now is 45.5.

[ptjones]

It helps having a ScanGuage because of the digital read out. Easier to see what's happening. To me the new system does feel like it is holding back all the time. Also this system feels quite different from the two EH(2008,2010) I had. This one slows down going down hill at 40mpg. My LT average is 45.3mpg , 3.3k.

[acdii]

Here is my summary when I got home. I didn't think about it, but should have taken a pic of each summary when I stopped to fill up or get coffee.

 

This is using the ACC set to 62 for a good portion and 65 the rest. 62-65 had the exact same results.

[acdii]

This is the most I see during the trip when at 65, it never goes any higher than just under 40 except when going downhill and its braking.

[LadyDi]

Pardon my ignorance. What does ICE stand for?

[jeff_h]

Pardon my ignorance. What does ICE stand for?

 

ICE - Internal Combustion Engine

EV - Electric Vehicle (mode)

HVB - High Voltage Battery (big one under trunk)

12v - 12v battery (little one in side of trunk)

SOC - State Of Charge

Edited July 20, 2013 by jeff_h

[GrySql]

When your FFH is running on ICE only at approx 55 MPH what instant MPG are you seeing... My ICE only runs at about 18-20 MPG at 55MPH

Same here, I think I posted somewhere else that 55 mph is one of the worst speed zones for my car, I avoid it if possible.

 

That feeling that has been expressed of 'a holding back' is one that my car has exhibited since new.

At times I've even stopped to see if I had a low tire, plus certain highway or road surfacing really lowers my mpg's.

I just associate it with the 'Charging Mode', tire friction and that 'unknown' that is built into some of these FFH's.

 

Brake drag doesn't factor for me, my car was just inspected and the brake pads/rotors were measured at almost new spec's @ 10k miles.

[djminfll]

I had been keeping my highway speed at 60-62 up until I started reading some of the posts about driving at 65-70 which allows the battery to charge more completely, and instant mpgs of over 40 are attained. I have been doing that for the last few days, and I am getting better fuel economy. I am going to see how this effects an overall tankful to determine which method will net me better results.

[kuzzi]

Quick 45 mile trip today and the ICE did well at 65 mph. Not too hot outside so battery wasn't taxed for AC. First 20 miles, instant readout was 39-40mpg after the HVB reached full charge at cruise. After the engine warmed up, the last 20 miles had 45 mpg at 65mph. I really like this engine.

[acdii]

There are times and certain roads that if I let the car stay one ICE and get the pack charged up I see 40-50 on the instant while doing 55. Drawback is that the time it took to get up to that charge I was doing 20 MPG so in reality I was getting about 30 MPG.

[hybridbear]

ICE High mode going 65+ MPH is great for long distance trips on the highway. For short highway trips it's better to drive below the EV threshold and let it cycle. Because of how long it takes the ICE to get into ICE High mode it's better to save it for just long trips.

[djminfll]

There are times and certain roads that if I let the car stay one ICE and get the pack charged up I see 40-50 on the instant while doing 55. Drawback is that the time it took to get up to that charge I was doing 20 MPG so in reality I was getting about 30 MPG.

Yes, that is what I have been finding as well. I did a couple of highway trips where I only had to go one or two exits, and it dropped my overall for this tankful. This is actually one of my worst fill-ups, mostly due to the rain that caused me to have to drive very inefficiently. :banghead: I'm only at about 200 miles on this fill-up, and I have barely broken 40mpg. It was running at about 35mpg until yesterday and today when I had 2 trips at 48 and 51mpg that brought the average up to 40.5. I will only exceed 62mph on the highway when I am going a longer distance!