Why a Hybrid Vehicle Loses Acceleration and Power–and How to Fix It

2017 Ioniq HEV. Image courtesy of Hyundai Global Media.

2017 Ioniq HEV. Image courtesy of Hyundai Global Media.


Other than questions about declining fuel performance, customer concerns regarding losing acceleration in their hybrid vehicles are voiced most frequently when they visit our authorized dealer network for The Hybrid Shop. It’s definitely a common issue, especially among hybrid owners with cars that are three to five years old.

The Two Systems that Impact Hybrid Vehicle Acceleration

With traditional cars, there is just one propulsion system on board – an engine fueled by gasoline. With your hybrid car, you have two.  Just like a traditional car, you have an engine – but you also have an electric propulsion or traction system and both of these work together to move your car down the road.

One of the problems that may be occurring is that the battery pack is actually low on energy and/or power. So, when you’re accelerating between 0 and 30 miles an hour, the vehicle heavily depends on the electric traction system to propel the vehicle down the road. If the battery pack is not able to provide the energy and/or power to the electric motor, which is imperative to moving the vehicle, you will most likely feel things like shutters or hesitations in the car. The most common description our dealers get from their hybrid customers is, “It feels pretty sluggish”.

So, outside of the normal issues with the vehicle, for example: the engine system, fuel system or the ignition – you can also have issues on the electric propulsion side with the battery not providing enough energy or power to the traction system.

From an MPH Viewpoint – Where Your Vehicle Loses Acceleration is Important

One of the important factors The Hybrid Shop dealers take into consideration when diagnosing a loss of acceleration is where on the speedometer that loss occurs. Pinpointing where that loss initiates can help determine which of the two propulsion systems is the root of the cause.

If you divide the speedometer reading into three segments, the diagnostic approach works this way:

  • Between 0 and 20 miles an hour, the system is relying heavily on the electric motor to propel the vehicle. In this segment, it’s roughly 80% electric.
  • In the next segment, 20 to 40 miles an hour, there is a balance between the engine and the electric traction system and this remains pretty constant through this range. Here, it’s typically 50% electric and 50% engine.
  • Once you get over 40 miles an hour, the system is typically relying on the engine to move the car.  On this end of the range, it’s roughly 80-90% engine


Regardless of where your hybrid vehicle’s acceleration loss is occurring, The Hybrid Shop dealers have patented technology and equipment to identify exactly where the problem lies. Their focus is to properly identify the cause and provide customers with the best solution for their acceleration issues.


This is more valuable information from TheHybridShop.comHECN is happy to welcome the TheHybridShop.com, a new green automotive startup, as our first Service Advisor.  The mission of The Hybrid Shop is to “provide the highest quality maintenance, service and repair experience for hybrid electric vehicle owners.” Read more about them and servicing hybrid electric cars here.  You can also find them on FacebookTwitterLinkedINGoogle Plus, and YouTube.

Next: Who Should Repair My Hybrid Battery, the Dealer or an Aftermarket Specialist?

Previous: Can a Poorly Performing Hybrid Car Battery Be Fixed?


Click here for reuse options!
Copyright 2016 Hybrid and Electric Car News
Paste your AdWords Remarketing code here