EV mode, speed loss

[Harry Burk]

We just purchased our ES300H, our first Hybrid. When the car selects EV mode on level ground there is a slight reduction in speed for the same throttle position. Almost impossible to maintain speed because when I very slightly increase throttle it kicks out of EV mode prematurely. Seems to me to be a programing algorithm glitch. Going into dealer to see if we have the latest software.

Burk .

[1990LS400]

Did you read the section about EV mode in your owners manual?  It starts on page 139 of the 2019 Lexus ES300h owners manual which you can view online at https://drivers.lexus.com/t3Portal/document/om-s/OM06178U/pdf/OM06178U.pdf

It's probably working normally.  One has to really "baby" the throttle to stay in EV mode in a non-PHEV Toyota hybrid.  I've experimented with keeping my wife's Prius in EV mode as long as possible but can't after I drive out of our cul-de-sac due to very slight upward slopes in both directions and needing to go fast enough to avoid antagonizing or getting rear-ended by other drivers.  A limitation of non-PHEV hybrid Toyota/Lexus vehicles sold in the North America seems to be their Ni-MH traction batteries.  The same vehicles sold in Europe with lithium ion traction batteries have longer EV ranges at higher speeds. 

EV mode is more useful when the vehicle is just barely creeping along or not moving, e.g. entering/exiting our garage, when stopped at a traffic light or otherwise "idling" and waiting.  I like how I can be waiting in line for a car wash bay on a hot summer day in silence with the hybrid system in EV mode and the interior being cooled by the all-electric A/C system.

We like EV mode a lot and are leaning towards replacing our 2012 Prius with a 2021 RAV4 Prime plug-in hybrid which should become available later this year - it is supposed to go up to 40 miles at normal street/highway speeds in EV mode before the ICE kicks it.  The RAV4 Prime will have a lithium ion traction battery like most PHEV's and full EV's.  40 miles is far more than my wife drives in a typical day.  We're also considering the upcoming Tesla Model Y but aren't willing to pre-order without a test drive.  A range increase to 320 miles was recently announced for the Model Y.