Hello friends. I own a HCH 09 and i am a really happy driver , as i am very pleased with my car. But i have a question and i would like your help for it.
Every morning as you know the EV assist wont work for the first minutes , less in summer , more in winter. What i dont know is what determines when the assist is turned on as this greatly affects the mileage of my car , ecpecially the days when my only driving is from home to work. I have tried various driving styles ( speaking of days with the same external temperature ) and i have noticed that , sometimes without an obvious reason the EV turns on after about 6 Km or 15 minutes of driving at an external temperature of 8-12 deg C , some other (few )days it happens after only 2-3 Kms. Anyone knows what we can do to minimise this distance ?

 

The engine temp has to be at 140 F for that to happen. the colder the engine, the longer it takes. When it was -8 F below here (than goodness only one day) the engine never got warm enough for auto-stop even after 25 minutes.

In Canada, most HCH have engine block heaters that keep the engine at about 120 F so it only takes a minute to heat up even in the dead of winter.

You can add one to you HCH and if you keep it plugged in - the time will be in the minute range.

 

Block heaters really help, good for your engine's longevity as well. Another thing you can do is partially block the grill. MSantos has some guidelines here:

http://www.cleanmpg.com/forums/showthread.php?t=17560

I find starting by blocking the upper grill most beneficial. I think it tends to hold the heat in the engine bay most effectively.

 

I didnt mean the auto stop friends , i meant EV assist. Even so , i have noticed that some days it begins sooner and some other days later ( assuming the outside temperature is the same ) and i wonder if anyone has found a reason why it is happening. I guess it has something to do with driving style but i cannot find a specific way how.

 

Full Charge/Assist and AutoStop tend to come on around the same time, and both starts are coolant/engine temperature driven. Assist only is available from start up. So if your Charge/Assist start times vary, it's a safe bet your warm-up times vary. Hit the "Display Change" button (just to the right of Sel/Reset, the tandem buttons at lower left corner of gauges) to toggle between instant mileage and coolant temp display: you can see temp climbing there. It invariably gets to halfway up and stabilizes there. Until it does you will get Assist (but no Charging), and likely no AutoStop.

 

I tend to agree with what others have said already. One other thought is whether your state of charge is at the same level at the beginning of your daily drive. I believe the IMA is less willing to assist when the state of charge is low (4 bars or less).

Try watching how quickly the coolant temperature rises. You should see 3-4 bars within about 2 kilometers in above freezing conditions. Another suggestion is to turn the climate control off until you see the coolant temperature rising to 3+ bars.

Even though your car is still very new, it may have a faulty thermostat. You should notice the temperature rising fairly quickly and then stabilize at around 9-10 bars (a bit below mid-range). A stuck thermostat is a common problem and will explain a slow warm-up. It's an easy repair if needed.

Cheers,

Roger

 

I think this is what youre looking for:

http://www.cleanmpg.com/forums/showthread.php?t=13570

ks