The FEH/MMH does not do a charge/discharge cycle to warm the battery and it's not getting a battery conditioning either. It all sounds like cold weather effects to me, but you could have a problem. It sounds like the battery is too cold to charge or discharge and your not getting electric motor assist. Are your tires at the proper air pressure and not packed with snow, mud or ice? This could cause extra drag on the engine and higher RPM. Do you park over night outside or use a block heater? Have you winterized your radiator with a block?

GaryG

 

Hi Gary,

Yup. wheels are clear of snow, we have not had that much yet anyway.. Emergency brake is off.. (that was one of the first things I checked)

Just heard back from the dealer... they say "engine speed is not related to the speed of the vehicle. It is related to the electrical requirements. of the battery, and it is operating normally. "

I've asked to speak to the technician, because that can not be right... If the batteries require the engine to turn that fast to charge them all the time, there is something wrong with the batteries. Even after a 3 hour run around town it still does it.

FWIW we do park outside, and have not started using the block heater yet...
Gary.. when you say "Have you winterized your radiator with a block?" do you mean blocking part of the from of the Rad with something to reduce the amount of cold air passing across it?

Thanks
Dean

 

I agree with your dealer somewhat because the engine RPM is not related to vehicle speed all the time. Engine idle in your '08 is controlled by MG1 (the small motor/generator) and if it is not charging the battery or controlling engine idle, your idle is controlled by the PCM only. You can see this in a neutral coast where there is no power going into or out of the electric motors. This idle is generally above 1,500 rpm and called a secondary idle.

Your problem in my opinion is a very cold battery that never gets a chance to heat-up enough for a charge or discharge. If the battery can't take a charge or is full, your not going to heat it up much because that requires charging. Since it's too cold to drive in EV, the only way to break this discharge problem is electric motor assist from acceleration. The best way to warm a battery is to drive in EV to lower the battery SoC before parking at the end of the day. The next morning your engine will go through a engine warm-up strategy which retards the engine timing to heat-up the CAT converter for emission purposes. During the warm-up strategy the electric motors provide power to the wheels and the engine remains at a high idle. The battery can drain down further than normal and therefore heat-up higher while recharging after the warm-up strategy. You must maintain heating the battery by recharging so that means you'll need to drive in EV as much as possible. Here is where the full radiator block comes in by keeping the engine temp hot enough to drive in EV. There is a technique I found a few years ago to go EV with a cold or hot battery. If the engine has met all the conditions to go EV, shift to neutral and tap the brake pedal to go EV. Shifting to neutral eliminates regen (charging the battery) which is causing the problem of going EV with a cold or hot battery.

Use your block heater on a timer for 3 hours prior to a morning start. Read up on the many threads here on radiator blocks and try to drain your battery as much as possible the night before. Once you block your radiator correctly and the engine stays warm, do the brake tap in neutral while moving under 40mph to go EV with a cold battery.

GaryG

 

Gary, Thanks for the insight. We've only had our Hybrid since March, and during the summer things were great... there is so much to learn to get the best performance out of the hybrid, and we are still learning...

Example number one... I was under the impression that both the Electric and Gas motor were connected to the wheels through the CVT some how. What I found out yesterday is that this is not the case. The Atkinson Cycle engine is only used to turn the generator to recharge the batteries. All propulsion is proved by the electric motor.

Also the CVT is really an ECVT.. ( there is no traditional transmission as such it is all electronically controlled).

We had a 30 minute conversation with the Hybrid tech yesterday and learned so much... Most of which was contrary to what the salesman told us. Not that knowing the truth would have changed our minds, but knowing more now, explains a lot about how the vehicle behaves.

Anyway.. thanks to Gary for the feedback, and I will definately be on this forum a lot in the furture learning as much as I can, and hopefully some day, I'll be able to return the favour.

Cheers
Dean

 

Dean,
This is only true in reverse. When driving forward both the ICE and one of the electric motor/generators (there are two, the second one makes the eCVT function) can supply power either separately or in parallel.This is true

JeffD

 

Hi Jeff..
I've definitely got a lot to learn... My brain is starting to hurt...

Cheers
Dean

 

One last thing to note is while in EV in Drive, both motors (MG1 & MG2) can drive the wheels forward.

GaryG

 

Typical, and the tranny is a planetary gear set. There is NO slipping of clutches, etc., because there is nothing to slip in it. It's normal, as is it revving up as you come to a stop after a long coast down a hill