So, you’re saying difficult starting is an artifact of the Miller cycle engine?
Car has to sit long enough to allow the stored coolant to cool off first. Plugs have to be worn and some buildup on the throttle plate. The way the valve timing affects compression along with deposit flow loss can cause a no start.
ANY vehicle (hybrid or not) may have problems in those conditions. So the solution is to FIX those problems…NOT replace the gas to 87 octane.
Agree. Not only does the gas engine conform to the same cold weather starting demands as any gas engine but the nichol metal hydride battery used for the drive motor is affected little by cold weather. So, at least from that POV and considering the starter/drive motor is also started by a traditional battery, there is collectively no reason why it should not start well as designed.
It being an Atkinson cycle engine is where the difference is vs most other cars.
Our 2006 Hybrid Escape has never had any starting problem, even in cold Colorado weather. Your friend should have this checked out because although hybrids are generally reliable, they can be very expensive to fix if they need repairs for hybrid-specific items (including electrical systems), and perhaps your friend can prevent this by acting early.
If you are buying a hybrid and plan to use it in bad winter weather, though, here’s one piece of advice: our Escape had eco-tires, and the Escape’s originals were the worst ones we can remember for winter weather or wet weather. We put regular tires on ours and it was like driving a different car. The newer eco-tires may be better than ours were, but you may want to research this before winter sets in. Alas, the mileage did go down after we replaced the original set, and it went down substantially in the winter.
It being an Atkinson cycle engine is where the difference is vs most other cars.Otto...Diesel...Atkinson...Miller...Sterling...I knew it was ONE of those guys!
You need very little compression for an engine to start,unless its a diesel and you need the heat,I think the old spark ignition kerosene burners had a 3 to 1 compression ratio,a good many engines actually have a compression release built into the system for starting and some have a button to push to reduce starting effort,if you have a cylinder full of schiometric gas and air all that is necessary for ignition is the spark-but that is not to say that some engines may be quirky about circumstances relating to initial ignition.
The current Prius doesn’t store heated coolant like the previous generation did, so I don’t think that can be a factor. For older ones, maybe. Anyhow, if this was a common problem we all would have heard about it years ago. The early anti-hybrid skeptics would have been all over it.
On the topic of premium fuel causing cold start problems for vehicles designed for regular this information is from a service bulletin published in 1997;
SYMPTOM/CONDITION:
Long cold start times, warm-up sags, hesitations, and driveway die outs. These symptoms are most noticeable and severe at moderate ambient temperatures between 4 - 27 degrees C (40 - 80 degrees F).
DISCUSSION:
Gasoline with a high Driveability Index (DI) can cause the above described symptoms. DI is a measure of the gasolines total volatility, or tendency to vaporize completely. A high DI number is less volatile than a low DI number. Most premium gasoline sold in the U.S. has a higher (worse) DI index than regular or mid-grade gasoline. Use of premium gasoline is NOT recommended for vehicles designed to run on 87 (R+M)/2 regular or 89 (R+M)/2 midgrade gasoline. High DI gasolines also cause higher emissions for the same reasons they cause driveability problems.
For vehicles that require an octane rating of 91 (R+M)/2, premium is recommended, or possibly required. Using premium fuel with a higher than recommended octane rating is not recommended. Owners who experience fuel related cold start and warm up driveability problems should try a gasoline with the recommended octane rating or different brands of gasoline until they find one that provides good performance.
The octane quality of gasoline is only a measure of its resistance to spark knock. The use of higher than recommended octane gasoline under normal operating conditions does NOT improve startability, idle quality, fuel economy, driveability, acceleration, engine durability, or emissions. In fact, most higher octane gasolines available in the U.S. have higher DI values than regular gasoline. Customers are most likely to experience poor driveability with premium gasoline than with regular.