lexitaxi

Hello Everyone,

I was hoping someone with a RX 450h could answer this for me.... searched the site, but didn't find any results.

For warming up a car on these frigid winter days, does remotely starting a Hybrid warm the cabin similar to a traditional car? When you start the car with the remote and let it "idle" for a few minutes to warm up, does the ICE stay on the entire time to warm the cabin, does the cabin warm via the batteries or is warming up the cabin of a hybrid a non-event because it doesn't warm until you begin to drive.

Sorry for such a silly, trivial question, but the geek inside of me wants to know if remote starts are worth getting on a hybrid.

Thanks!

kitlz

I can't say the 450h gets as warm as it should using remote start but every little bit helps. The RX still has that few second delay before the engine turns on. I notice ICE kicking in sometimes when it's especially cold like right now. But the engine still shuts off every once in a while. Per the dealer, the best thing to do is drive to get the heat going. Oh, and turn off eco mode. I let mileage suffer instead of me

cossie1600

Hybrid heats up quicker and therefore it can shut off the ICE quicker.

Calling All BTUs

Another key to improvements in fuel economy comes from the Exhaust Heat Recovery System. An important part of the hybrid control strategy is to stop the engine when it’s not needed, for example in low power demand conditions in city driving. But in winter driving, engine heat is needed to warm the interior cabin and demand on the electric drive motors will be naturally higher in these conditions, especially during warm-up. When temperatures drop below 0° C, battery output is also reduced and drive motor performance suffers accordingly.

To counter this challenge, Lexus developed an efficient system that recovers exhaust heat to quickly raise coolant temperature during warm-up. This allows the engine to stop sooner, helping to improve fuel economy during this phase. For example, testing at -5° C on a typical driving pattern (below) showed that the engine could be stopped a full 1,000 seconds (over 15 minutes) earlier than the previous model.



Exhaust heat is recaptured from the exhaust pipe just downstream of the catalyst where a recovery unit is mounted directly on the exhaust system. A thermostatically controlled valve forces part of the exhaust gas to re-circulate in a chamber, heating the surrounding coolant quickly. A spring in the valve allows it to open during full acceleration. When engine coolant warms sufficiently, the valve opens to allow exhaust gas to bypass the heat recovery system.

Droid13

To the original question, provided the climate system is set to on (and yes, better if ECO mode is off) then the engine should run for several minutes at least. If the heat system is off, the engine is likely to shut off fairly quickly, even without being warmed up. Actual driving is, as mentioned, the best way to warm.

I am actually a bit surprised how long it takes my RX450h to warm up, especially given the exhaust heat recovery system. My Camry Hybrid did not have such a system, but it warmed up pretty quickly even at freezing temperatures. The temperature gauge would start moving within a minute or two and usually reach it's "warm" position in about 5 to 10 minutes. The gauge in the RXh doesn't even start moving for at least 5 minutes or more. I know the temp gauge on the Camry was not linear, not sure what the RXh does. On my to do list is to use the Torque app on my phone to monitor the specific coolant temperature and compare it to the gauge positioning. I am curious to see at what temp the gauge actually starts to move.

lexitaxi

Thank you all for the information!

DunWkg

I believe climate control temperature settings are memorized and associated with a key fob when you set the memory position for your seat and mirrors.

Meaning, if you had the temperatures set low or average when you memorized, then when you remote start with that fob the settings will revert to those settings. If you had the settings set high (hot) when you memorized, your car maybe warmer when you get in. Assuming of course your engine is warm enough to generate heat for the interior.

wyau01

Not sure if Toyota uses synthetic motor oil, but it does in a Lexus.
Synthetic motor oil takes longer to warm up.