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Hi guys, I hope someone can shed some light as to whether my car is running OK or not!

When driving at cold temperatures below 6C I notice that my GS450h runs more on the engine and hardly the hybrid system.

When I park up the engine keep running until I turn off the car!

I've had it plugged into techstream and there are no error codes!

Is there something to be worried about?

Many thanks in advance.

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I would say its normal that engine would work more on the cold days - to compensate for temperatures and keep it warmer. Fuel consumption is in nearly all cases higher in colder days on every car. 

Got the same situation now when we have temperatures around 2-5 degrees. Still goes on hybrid, but more often engage regular engine. Also engine temperature tend to go lower faster while on ev only, so it kick in sooner to hit back operating temps

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3 minutes ago, Zabe said:

Hi guys, I hope someone can shed some light as to whether my car is running OK or not!

When driving at cold temperatures below 6C I notice that my GS450h runs more on the engine and hardly the hybrid system.

When I park up the engine keep running until I turn off the car!

I've had it plugged into techstream and there are no error codes!

Is there something to be worried about?

Many thanks in advance.

It will not run on the Hybrid system unless there is sufficient power stored. Look at your screen showing fuel consumption. I reckon that what you are experiencing is normal Zabe. Same as mine.

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Nothing to worry about and perfectly normal.

The petrol engine is the only source of cabin heat so as temperatures get lower and you turn up the heater, so the engine will run longer and more often. Plus, as Bart says above, all cars will increase fuel consumption during colder weather.

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1 minute ago, Herbie said:

Nothing to worry about and perfectly normal.

The petrol engine is the only source of cabin heat so as temperatures get lower and you turn up the heater, so the engine will run longer and more often.

Great point here, cabin temperature is important - higher you go, engine work more often. 

Many times I raise heat by 1 degree inside and that kick in engine and if I flip it back same moment goes back to ev. 

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Many thanks for the reply guys. So the car will do this even though the batteries show green bar or max on blue bars on stored energy?

Also why would the engine be running on park after approximately an hour drive when the climate control is not set for any heat? 

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43 minutes ago, royoftherovers said:

It will not run on the Hybrid system unless there is sufficient power stored. Look at your screen showing fuel consumption. I reckon that what you are experiencing is normal Zabe. Same as mine.

Thanks for the reply and input. The batteries were showing 1 bar green charge so surely this would have been enough? 

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48 minutes ago, Kijan said:

I would say its normal that engine would work more on the cold days - to compensate for temperatures and keep it warmer. Fuel consumption is in nearly all cases higher in colder days on every car. 

Got the same situation now when we have temperatures around 2-5 degrees. Still goes on hybrid, but more often engage regular engine. Also engine temperature tend to go lower faster while on ev only, so it kick in sooner to hit back operating temps

Thanks for the reply. Any ideas as to why the engine keeps running when parked up then?

Last night after driving for approximately 1 hour I parked on my drive and noticed the engine just kept running and very very slowly lowering the HV charge on the Battery.

The climate control was not set for heat or A/C.

I just turned the car of myself from the button. 

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It sounds as if the engine wouldn't be running to provide heat if you have the climate control turned off. One unlikely possibility is that you've been going down a long hill and the high voltage Battery has been charged to maximum. Even when the car stops, the car may reduce the Battery charge by using the electric motor to spin the engine without fuel. What you hear sounds like the engine running but it isn't running on fuel. I would think this is unlikely unless you routinely take a route down a long hill.

(Edit: your last post says the charge level goes down, which makes this explanation sound possible.)

On the other hand, when the Battery is low the engine will run, even when stationary, to charge up the Battery. On the IS, the engine will start when the Battery goes down to 40% charge (two bars on the meter) and the engine will stop, around four minutes later, when the Battery reaches 50% (three bars on the IS).

Do these possibilities fit with any of your scenarios? The 2007 GS450h may be a bit different from my experience with the IS300h.

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2 hours ago, Thackeray said:

On the other hand, when the battery is low the engine will run, even when stationary, to charge up the battery. On the IS, the engine will start when the battery goes down to 40% charge (two bars on the meter) and the engine will stop, around four minutes later, when the battery reaches 50% (three bars on the IS).

Do these possibilities fit with any of your scenarios? The 2007 GS450h may be a bit different from my experience with the IS300h.

Have the same pattern on low Battery in MK4 GS450h - down to 2 bars, then kick in to charge up to 3 and shut off moment after until its drained back 

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3 hours ago, Thackeray said:

It sounds as if the engine wouldn't be running to provide heat if you have the climate control turned off. One unlikely possibility is that you've been going down a long hill and the high voltage battery has been charged to maximum. Even when the car stops, the car may reduce the battery charge by using the electric motor to spin the engine without fuel. What you hear sounds like the engine running but it isn't running on fuel. I would think this is unlikely unless you routinely take a route down a long hill.

(Edit: your last post says the charge level goes down, which makes this explanation sound possible.)

On the other hand, when the battery is low the engine will run, even when stationary, to charge up the battery. On the IS, the engine will start when the battery goes down to 40% charge (two bars on the meter) and the engine will stop, around four minutes later, when the battery reaches 50% (three bars on the IS).

Do these possibilities fit with any of your scenarios? The 2007 GS450h may be a bit different from my experience with the IS300h.

Thanks for the input but unfortunately its very different to what I'm facing!

My Battery has more than enough charge but the petrol engine stays on.

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14 minutes ago, NemesisUK said:

The engine will also run to maintain the designed fluid operating temps, even if the climate control is off the engine needs to keep itself warm to operate efficiently 

Ah that's a very good point. It might be that during really cold weather! 

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It's interesting in that both my RC models the engine will fire up after an overnight stop within 10secs of Ready mode (unless I invoke EV mode) but the car is moving under electric power. The engine is running but isn't under load. I can watch the Battery bars reducing and on reaching 2 bars the engine note changes and I feel a slight sure in drive (I have a steep uphill from my house).

I'm sure the ICE fires up to warm itself and the fluids, even in mid summer when there is no heat required for the cabin, just to be ready for when the traction Battery needs a recharge (which obviously is quite soon). I guess it's all to reduce wear (not to load the engine until warm)  and improve efficiency

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49 minutes ago, Zabe said:

My battery has more than enough charge but the petrol engine stays on.

Are you sure the engine is actually using fuel? Have a look at the Hybrid Assistant app, which will tell you if fuel is being used. I may have misunderstood your description but it seems

  • (a) the car has been running for an hour and should be fully warmed up,
  • (b) the high voltage Battery is virtually fully charged,
  • (c) when the car is parked after the long run the engine keeps turning when the car is stationary and
  • (d) the charge in the high voltage Battery goes down as the engine keeps turning.

My guess would be that all this points to the hybrid system deciding to reduce the charge in the Battery from what may be close to its normal maximum. It does this by drawing on the electricity in the Battery to turn motor-generator 1 (MG1), which in turn spins the petrol engine without using any petrol. This reduces the charge of the Battery from its maximum.

But if you find that petrol is being used when the engine spins while the car is stationary and at the same time the charge in the Battery is going down, there must be another explanation.

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55 minutes ago, NemesisUK said:

It's interesting in that both my RC models the engine will fire up after an overnight stop within 10secs of Ready mode (unless I invoke EV mode) but the car is moving under electric power. The engine is running but isn't under load. I can watch the battery bars reducing and on reaching 2 bars the engine note changes and I feel a slight sure in drive (I have a steep uphill from my house).

I'm sure the ICE fires up to warm itself and the fluids, even in mid summer when there is no heat required for the cabin, just to be ready for when the traction battery needs a recharge (which obviously is quite soon). I guess it's all to reduce wear (not to load the engine until warm)  and improve efficiency

Yes, I was surprised to find that if you drive away straight after starting the car, you're actually using power from the Battery initially rather than from the engine until it has gone through its multiple warming up stages. The Hybrid Assistant app tells you which of the five (or six) warmup stages the engine has reached. (Sorry for another plug for Hybrid Assistant!)

Here's a link setting out more than most people want to know about the engine warm-up stages.

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Zabe when parked up in the situation you describe look at the MPG on the dash if it goes down it confirms that the engine is indeed running and using fuel rather than being turned by the e/motor to intentionally reduce Battery.

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37 minutes ago, Sherra said:

look at the MPG on the dash if it goes down it confirms that the engine is indeed running and using fuel

A good idea!

It would be good to know how long the engine runs. If it's only half a minute, it might not be long enough to register on the mpg, though.

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27 minutes ago, Riccccccardo said:

Probably already been said here already what I’ve noticed when cold outside so you put the heater on the engine will Inevitably run more in engine mode just the way it is as heater uses a lot of energy. 

The engine will run because it's the only source of warmth (from the engine coolant) for the cabin, nothing to do with using more energy.

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