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Discussion Starter · #1 ·
How come the petrol motor kicks in at the traffic lights when the motor is well and truly warm and the battery is high on charge.

Any help is greatly appreciated.
 

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My first thought would be that the engine temp was not high enough for the catalytic converter. And next, The MFD is more of a conversation piece and really is not any exact indication of battery charge. Doesn't even indicate half of engine run times.
The engine runs when the computer says it has to run. Probably dozens of reasons.
That should satisfy anyone who would buy a car with no instruments in it.
 

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too much engine

The engine will initially run until the catalyst is hot enough. It will run again if the big battery happens to fall below a particular level of charge. Air conditioning and defrosting seem to make it particularly liable to running. It will start again whenever the power demand from the accelerator pedal cannot be readily supplied by the electrics.

Coded, if you want to learn more about this car there is much info hidden aaway in prior messages here, and in the other internet discussion groups.

DAS
 

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First, I will be assuming we are not talking about the classic.

If the car is stopped, and the ICE was not running when the car was stopped, and the battery level is between 3 and 7 bars, and there is no heat demand from the cabin, I see no reason for the ICE to start while still stopped.

If the ICE was running entering into the stop, it may continue running for a bit, then if SOC is sufficient, and no heat demand of the cabin, it should stop within a minute or so.

If SOC is 2 bars or below, ICE may start to maintain proper battery SOC. If it is teetering at the the 'must charge' threshold, ICE may seem to not be able to make up its mind, especially if you are crawling in traffic.

If SOC is 8 bars, the car may stop and start the ICE to bleed off the excess SOC. Once it gets down to 7 bars it shold stop doing this.

If this IS a classic, the compressor is mechanically driven by the engine as it is on a conventional car, so if the compressor is needed, the ICE will start.

SOC = State of Charge of the battery.
ICE = Internal Combustion Engine.
 

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Isn't it currently winter in Australia? You didn't say if you were in the hot north or cold south.

As DanMan said, if there is a demand for heat, the ICE could very well startup while stopped at a light.
 

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Discussion Starter · #7 ·
RealAle said:
Isn't it currently winter in Australia? You didn't say if you were in the hot north or cold south.

As DanMan said, if there is a demand for heat, the ICE could very well startup while stopped at a light.
We are in the warmer part of Australia. Customer has stated that the vehicle was on highway for 20 minutes and then town for 10 so should be warm enough you would think ??
 

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Sometimes yes, sometimes no. How warm is warmer part of Australia?
If heat demand is max heat, or defrost is set on, that could trigger the ICE to run without moblility demand. To see if climate control is the issue, try turning it off for several seconds when ICE is running at a stop and see if it won't shut off.

Sometimes I do find that even after driving at an average of 45 MPH for 30 minutes, when I reach my co-worker's house to pick him up, ICE is often running and continues to do so for about 10 or so seconds.
Come to think of it, it might have to do with the fact that I have to drive trough his complex doing about 10-15 MPH for about 1000 feet, so ICE may have cooled down a bit at that point.
 
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