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Discussion Starter #1
Has anyone else noticed that there is a delay between pressing the "go" pedal and the electric motor picking up? It isn't all the time. It seems to only show when the system is in regeneration. It is as if it has to spend time coming out of regen mode and into acceleration mode. If is it already in acceleration mode then there seems to be no delay.

The delay period varies and I have yet to determine what the determining factors are but on one occasion there was a good 2 second delay between me pressing the pedal and us starting to accelerate! I was going to pass a car but by the time we started to pick up speed I had to back out of the manoeuvre. Very disconcerting.

Sally was with me. I mentioned it to her and we tried to recreate it and that was when we discovered that the delay on seems to be there if we are regen. Sometimes it is easy to over-estimate these periods of delay but Sally was with me and she timed one of the delays at about 2 seconds.

It has always happed for me and that is why I have never thought to mention it before but I generally don't drive the car that aggressively so it is very rare for me to need power that quickly but today's event made me worried that power wouldn't be there is I needed it in a hurry for some reason.

I would be very interested to hear if others have this phenomena. I am wondering if I should take it in to get it checked out but I can see it now... they will either not be able to recreate it because they don't drive it is a way that allows it to occur... or they will say it is normal!
 

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Yes mine does it. In fact the Voltec system is known for this. You don't get the instant torque as with a BEV.

I've seen torque graphs that show a half second ramp up. There is sometimes also a delay before the clutches sort themselves out. This will be to protect them and the gear box from the instant 0 rpm torque.

I don't find it an issue because I anticipate it before making a move.
 

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Discussion Starter #3
Ah right... thanks David.

It has never been a problem in over a year and 15K miles so I can't say it will cause me any distress now that I know. I was just worried that there might be a problem. Clearly not then.

I will say though that is was a bit disconcerting though because I discovered it right when I needed the power NOW! Not 2 seconds later. Just something new owners might take note of :)
 

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Yes, mine did it today. Went to overtake a car and had about 1 second hesitation. Like you say Paul its a little disconcerting but is documented alot on the US forum so I am not worried!
 

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I also find you get a quicker response by feeding the power in gradually (i.e. over the period of a second) rather than stamping on it. Timings that I got at Santa Pod seemed to back this up.
 

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Mostly I get no delay, apart from my reaction time in the stats from Santa Pod above. I do notice a slight hesitation when in erev mode, I just put that down to average demand measurement and prediction algorithms.

I don't left foot brake - is that a factor?
 

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Discussion Starter #11
I don't left foot brake on the road. I used to race karts and cars and so left foot braking for me is pretty natural but I made a decision not to LFB on the road as I often switch between auto/manual/EV cars and it can get confusing <eeek!>
 

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I only notice a delay if in 'petrol' mode I have never had an issue with EV mode. I put it down to clutches and engine revs sorting themselves out since the engine can be connected to the drive train in petrol mode.
 

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I believe the delay happens above about 35mph when you've held a pretty much constant or reducing speed for at least 30 seconds. In that situation the car shifts from single motor to dual motor mode which is more efficient as the motors are running more slowly but has less torque available. When you try to accelerate there's a bit of delay as it switches back to single motor mode. Or when the petrol engine is running it's the same as it switches from parallel hybrid to serial hybrid.
If you think you're going to want to accelerate then you may be able to blip the go pedal in advance so you get instant power when you actually want it.
 
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