Unduly fast tick-over in Hybrid mode

[Smarsde]

I have a Hybrid Formentor VZ2 and am struggling to understand why the tickover gets and stays unnecessarily high when I switch to Hybrid mode or when I‘ve run out of electric charge and it switches to hybrid mode.

I’m talking of a tickover speed of over 1000 rpm sometimes between 1400 & 1800 rpm, when idle and even when coasting.

This can’t be right even though the dealership suggested they found no faults and this was normal behaviour for a hybrid to regenerate but I kind of think it’s overkill given the limited charge regenerating provides if that is the case, I.e. likely costing me more in unnecessary fuel burn to get me a little elec power.

Should I just trust it to get the right mix even though my instinct is it’s too high and surely can’t be economical not to mention the stress of the unnecessary noise. or is there some kind of setting in the regeneration settings that can alleviate this, I hve switched from automatic regeneration to low, not sure it’s made a difference?

Any advice appreciated.
thanks

 

[Karbonfaiba]

I haven't driven many hybrids that haven't had a raised idle speed tbh.

A large part of the reason is to always have the engine running within the most efficient power / torque curve, mostly for generating electricity, but I imagine on eHybrid, also for when the third clutch on the DSG engages the driven wheels, so the power doesn't die off.

The driving experience should at least be closer to ICE under normal circumstances with the DSG, as I understand it uses the third clutch more often for motion, whereas other hybrid systems i.e. Honda - the gasoline engine is even more subservient to electricity generation with exception for the "final gear" which is like an overdrive.

Mild hybrids would be closer to what you expect from a normal idling behavior as that's a type of hybrid where the electric motor is simply providing a boost to the engine but only when charge is available.

 

[CupForm]

stays unnecessarily high when I switch to Hybrid mode or when I‘ve run out of electric charge and it switches to hybrid mode

It's considered normal behavior of the ICE, if it's only doing that after the first start of that trip (from cold, not hot or warm engine). It is a way of reaching higher temp (and other normal working parameters) faster that if it would idle at about 1.000 rpm. I've seen it mentioned also in the case of non-hybrid engines of other manufacturers - keeping the revs a bit high after the first start in colder days.
I'm using my PHEV in EV mode most of the time for the daily commute, which means the ICE doesn't have too many chances of firing up. And when it does, it stays at high-revs for quite some time - even if there's no load on the engine. At this stage some users (myself included) noticed some vibration that's transmitted into the car body - that can be felt into the seat. That's something that goes away after some tens of seconds, and I'm under the impression it's related to the high-revs the engine keeps after firing up. The same phenomenon (vibrations after ICE start on PHEV) was mentioned also by users of more powerful hybrids from VAG (e.g. Touareg or Passat).
I'm assuming that in your case the revs are going down after a short while (2-4 minutes), depending on outside temperature, speed etc. - and that would be considered normal as I mentioned above. However, if you had a short stop (let's say at a gas station) with warm ICE and it still keeps high revs after restart, then it's something to investigate.
BTW, no need to change your regen to "low" - it has nothing to do with the ICE behavior that you mentioned. Just keep the setting that you enjoy most.

 

[Ian986]

I can have a look at our tomorrow but i think it does rev a little higher than you would think.

 

[Smarsde]

thanks all who’ve replied, its making sense to me now!

 

[Karbonfaiba]

I'm not surprised your dealership / sales agent didn't provide better technical advice... only interested in the green

The trouble is the word "hybrid" has been around a reasonably long time now, and it's always been more "manufacture interpretation" than any other category of vehicle.

I think EVs mostly share the same driving characteristics, sure some may have a 2nd gear, but that's about it. ICE mostly shares the same characteristics becoming a more performance or gearbox dependent conversation; i.e. torque convertor, DSG, CVT.
Mild Hybrid has better defined driving characteristics.

Hybrid is the only catch-all term only meaning the vehicle uses two types of energy sources.