Fuel consumption

[agent_dess]

Dunno im not impressed with fuel consumption.

This morning i travelled 1.5 miles and before i even reach 0.5 mile the range went from 193 to 191 and by the time i got back so total 3 miles it was 187 range does this mean it burned 6 miles of fuel on a 3mile journey? and yes i was light footed and mostly cursing along without touch gas pedal.... i will take the comp readout with a pinch of salt.

Its been running on E5 fuel.  My IS250 wasn't this bad.

It seems to be more time and energy is spent charging the Battery lol.. 

I have replaced all 4 spark plugs last weekend.

I could argue 1 factor in fuel consumption is the crappy Chinese branded tyres i have at the moment i will be replacing them in a few months.

 

[Moleman]

6 minutes ago, agent_dess said:

This morning i travelled 1.5 miles and before i even reach 0.5 mile the range went from 193 to 191 and by the time i got back so total 3 miles it was 187 range 

Did you have the heating on? If so the engine was likely running both ways to heat the cabin. Short trips will always appear be worse than longer trips. The average balances out over time. 

[agent_dess]

5 hours ago, Moleman said:

Did you have the heating on? If so the engine was likely running both ways to heat the cabin. Short trips will always appear be worse than longer trips. The average balances out over time. 

I have AC always on and set to 24 degrees at 2 bar fan speed.

[Moleman]

1 minute ago, agent_dess said:

I have AC always on and set to 24 degrees at 2 bar fan speed.

That would make the difference.

[Lex_1988]

Think it's pretty decent once the cabin and engine are warm. Early 40s is normal for a 10 mile+ trip. Anything shorter than 5miles and it's down to early to mid 30s in these temps. Not helped by the Mrs always using the heated seats... 

Overall with the non existent repairs and low tax, its such an easy thing to live with. 

 

[Jeff Leach]

I have noticed a big drop in the last month or so.  My reading was always 41/42 mpg. It has dropped to 35/37 mpg. I have not changed my driving style.

[Moleman]

11 minutes ago, Jeff Leach said:

I have noticed a big drop in the last month or so.  My reading was always 41/42 mpg. It has dropped to 35/37 mpg. I have not changed my driving style.

Seems reasonable for winter temperature change. Do you do mostly short or long trips?

[Jeff Leach]

Mainly short trips. This is the first time I have noticed, having had the car for 5 years.

[Moleman]

5 minutes ago, Jeff Leach said:

Mainly short trips. This is the first time I have noticed, having had the car for 5 years.

Perhaps the combination of winter and E10. 

[wharfhouse]

7 minutes ago, Moleman said:

Perhaps the combination of winter and E10. 

Before the cold weather set in I surprisingly found E10 was giving better fuel consumption in my IS 300h (I can't explain why either...! ). Cold weather masks a lot though - a fall in temperature from 15C to 10C has a big impact on fuel economy. Over 5 years and 70K miles and all types of driving all year my car has reliably averaged annually 48mpg (measured by the car computer) so will be interesting to see how it fares on E10 over a full year. 

[Thackeray]

23 hours ago, agent_dess said:

This morning i travelled 1.5 miles and before i even reach 0.5 mile the range went from 193 to 191 and by the time i got back so total 3 miles it was 187 range does this mean it burned 6 miles of fuel on a 3mile journey? and yes i was light footed and mostly cursing along without touch gas pedal.... i will take the comp readout with a pinch of salt.

If the engine was cold when you started it would have used a lot more fuel than when cruising with a warm engine on a motorway. Switch to the energy display that shows a fuel consumption graph minute by minute. If you watch this when you start the car from cold you'll see that it will be doing around 20mpg for around the first five minutes (or more depending how cold the weather is). But as the engine warms up you'll see the mpg rise to its normal level for the proper engine operating temperature. The engine goes through five phases of warmup which affect engine timing. So the best consumption won't be reached until it reaches the fifth phase, (confusingly this is called stage 4) which on a short trip it may never reach.

If you're interested in the engine stages, see this link, and scroll down to post number 7 by "Grumpy Cabbie".

[agent_dess]

While its not comparison but our Kia Caren (7 seater Diesel) made that same 3mile round trip on only 2 mile usage range with heating and fan set to max this morning.. i would expect much better from the IS300h.  Sure the reliability and £10 ved you can live with it but isn't the whole point of the hybrid for city i.e. short driving?

[wharfhouse]

12 minutes ago, agent_dess said:

While its not comparison but our Kia Caren (7 seater Diesel) made that same 3mile round trip on only 2 mile usage range with heating and fan set to max this morning.. i would expect much better from the IS300h.  Sure the reliability and £10 ved you can live with it but isn't the whole point of the hybrid for city i.e. short driving?

It is once the engine is warmed up - in the summer you will see a noticeable difference but even then the first mile or so is needed to get some heat into the engine. For such short (less than 3 mile journeys) I don't think you'll see much difference between petrol or diesel or hybrid - well only PHEV if you run it on Battery alone. 

[agent_dess]

31 minutes ago, wharfhouse said:

It is once the engine is warmed up - in the summer you will see a noticeable difference but even then the first mile or so is needed to get some heat into the engine. For such short (less than 3 mile journeys) I don't think you'll see much difference between petrol or diesel or hybrid - well only PHEV if you run it on battery alone. 

Fair enough 🙂
My next grip is the EV Mode.... i need to read the manual properly but i only manage to last about 20secs in EV mode, is there a max speed before engine takes over? what is the exact function of EV mode?

[wharfhouse]

3 minutes ago, agent_dess said:

Fair enough 🙂
My next grip is the EV Mode.... i need to read the manual properly but i only manage to last about 20secs in EV mode, is there a max speed before engine takes over? what is the exact function of EV mode?

Not of much use to be honest - never worth using on the move. The only real use I have found for EV mode is after you start the car in the first few seconds press EV mode. The car will then stay in EV even whilst the engine is cold allowing you to eg move the car around on the drive without the ICE starting up (so long as you are gentle with the throttle). Not sure how long you get before the ICE finally kicks in though and if you do anything other than light throttle movements the ICE wil kick in too...! 

[agent_dess]

Never mind the EV Mode:
 

 

[agent_dess]

One final question... when i start the car its silent for about 10secs then the petrol engine starts..  should you wait about 30secs after that for oil to flow though the engine before moving off?

In the is250 i always used to wait 30secs before moving off on a cold start to help reduce engine wear....

[wharfhouse]

8 minutes ago, agent_dess said:

One final question... when i start the car its silent for about 10secs then the petrol engine starts..  should you wait about 30secs after that for oil to flow though the engine before moving off?

In the is250 i always used to wait 30secs before moving off on a cold start to help reduce engine wear....

I've never bothered - just hit Start and move off

[Thackeray]

1 hour ago, agent_dess said:

when i start the car its silent for about 10secs then the petrol engine starts..  should you wait about 30secs after that for oil to flow though the engine before moving off?

Nothing you do makes much difference as the engine isn't used to propel the car for the first couple of minutes from cold. In the first stage of warming up the engine the car only moves on Battery power. You may think it's running on engine power because you can hear the engine. But if you look at the energy monitor you'll see that no power is flowing from the engine either to the motor-generator or to the wheels for the first minute or so. This happens even if the car won't let you switch on EV mode.

Below is the description of the first two stages of engine warmup, copied and pasted from the link I included in my earlier post. If this is more information than you wanted, the only advice might be not to accelerate too hard when the car has just started from cold. But ultimately, it's probably not going to make much difference.

Stage S1a:

• when the start coolant temperature is below 40C, the warming up starts and continues for approx 50 seconds after stage S0.
• you can not enable the EV-Drive Mode during this S1a.
• the ignition timing is very late, after the top dead center. therefore the engine does not have enough power to drive Prius or charge Battery.
• basically, Prius can not use the engine power when you drive. Prius is driven by Battery power and the Battery is discharged.
• it is good idea to drive slowly or stand still warming up in this stage.

• when the start coolant temperature is between 41C and 60C, Prius is in this stage, but the engine does not start automatically.
• when you press the accelerator (including driving), the engine starts and runs for approx 50 seconds or until the coolant temperature reaches 65C. the ignition timing is very late too.

S1b:

• this is an extended warming up stage.
• you also can not enable the EV-Drive Mode during thisS1b on Gen3. (you can enable the EV-Drive Mode on Gen2)
• the ignition timing is now normal, and the engine is able to provide power and charge Battery.
• you are now ready to drive without any penalty of Battery discharging.
• ( A ) if the the coolant temperature is still below 40C after S1a, the warming up continues until 40C.
• ( B ) if the the coolant temperature is between 40C and 50C after S1a, the warming up continues until 50C.
• ( C ) if the the coolant temperature is between 50C and 60C after S1a, the warming up continues until 65C.

[ColinBarber]

4 hours ago, Thackeray said:

Nothing you do makes much difference as the engine isn't used to propel the car for the first couple of minutes from cold.

Unless you request more power than the electric motor can provide, in which case the ICE will switch to providing power to the wheels directly. If it didn't do this then you wouldn't be able to travel faster than 50 mph in the IS300h in the first couple of minutes - which is incorrect.

Even once warm the hybrid system will try and only use electric power to pull away (again depending on how much power you request via your right foot).

[Mikey B]

Using the remaining range to calculate consumption will always be hit and miss - its an estimate based on how much fuel you are using - transversely you might only loose 2 miles when you have covered 5 if you are using less than the average i.e going down a hill in EV

[Las Palmas]

6 to 6.5 L / 100km is what our CT is using on most short tours (very short tours) and that is where temperature so far while we have been living here (since 2005) has not come below 15 C in the coldest of months at night. Car is parked in garage 2 storeys down so need engine power to get up. So far no problems with Battery or anything else. Filling the car and driving careful (slow) 80 km tour will show 5 L / 100km.

Lexus here tell us that is normal.

[GMB]

I get 14mpg, (whatever that is in metric) but if I drive carefully I can get 17 from my Lexus, my wife gets 27mpg from hers.

The price of Shell V power at the last fill-up was £1.63 per litre from our local rip-off garage. I think I will buy a push bike and annoy everybody by riding in the middle of the road.

I also always turn off the stop /start pain in the neck which turns the engine off then on at random. I wish I could disable it permanently. Can't find a setting for this option.

So, it's heating or eating or driving, only one of which is available now.

[DBIZO]

On 2/4/2022 at 12:44 PM, agent_dess said:

Fair enough 🙂
My next grip is the EV Mode.... i need to read the manual properly but i only manage to last about 20secs in EV mode, is there a max speed before engine takes over? what is the exact function of EV mode?

All EV mode does is that, if your traction Battery is charged enough and fully warmed up, it cuts off the engine (if it was running), and you can also accelerate a bit harder before the engine kicks in again. It's useful when rolling through a residential area at night, for example, or in cases you don't exhaust fumes somewhere.

It is not a proper EV mode because there is simply not enough charge in the hybrid Battery even if fully charged, to support a full EV run. The usable capacity of the hybrid system in the IS300h is probably a few hundred Wh, you can probably get a mile out of it if fully charged, which it pretty much never is. 

[Slicendice]

Does anyone know if there is a way to install a larger capacity EV Battery?