2018 Honda Clarity Plug-In Hybrid acceleration problems

Filed Mar 25, 2026 · Acceleration, Driver assistance · CA · crash · 1 injury

I had an unintended acceleration happen as I was easing into a parking spot of a covered parking garage. The car accelerated like a jet plane taking off. I jammed on the brake. The only thing that stopped the car was the concrete wall that was 4 feet away. My airbags activated. We had taken the car to the Honda dealer for its 35,000-mile check-up on February 24, 2026. The Honda dealer has prepared all maintenance, including Honda recalls, since we bought the car in 2018. I'm scared about what caused the unintended acceleration and concerned that others could be injured. Electronic throttle control? Cruise control? Sensors? Wiring problems? What activated it? I believe this is a Honda mechanical problem. I have researched online that others have had unintended acceleration problems with the Honda Clarity and CRV–another plug-in hybrid–but not enough claims to lead to a recall. I have gotten a runaround. Our insurance carrier has declared the car a total loss but refuses to have the computer assessed to determine the cause. The local Honda dealer says it’s not their problem, claiming that we would have to tow the car to them and pay them to replace all safety items. They would then reboot the computer and delete all data, so they could not assess the cause. They said the Clarity has no “black box.” I contacted American Honda Corporation's customer service. Their engineers would not look at the car either unless our insurance company asked and paid them to do it. I have that Case Number. You would think that American Honda Corporation would be concerned, particularly since this unintended acceleration could have killed pedestrians if it had happened on the street or killed me if the concrete wall had not stopped the car. We had the Honda Clarity towed to our house to see if we could find someone to check out the computer. The towing company has driven the car, even though the airbags were activated. After 30 days, our insurance company will take the car for salvage.

Filed Nov 14, 2024 · Acceleration, Electrical · ME

Several times now while driving on the interstate at the average speed of 70 to 75 which is the speed limit in my Area the battery level while fully charged it's supposed to only drop down to 20% I have noticed several times now while on the interstate I've been barely able to drive 40 mph as it is dropping the power level down to almost zero there is no bars being illuminated they're supposed to be two bars for 20% and even one bar for 10% and twice now in a matter of 2 weeks I've noticed that it goes down to zero bars and the engine is revving very very high and I have very little power available this is quite dangerous on the interstate and I wish this could be resolved or I'll be getting rid of this car

Filed Feb 6, 2021 · Acceleration, Engine · GA

Few times it has happened especially in extreme cold weather, there will be loss of power/acceleration even though you are trying to accelerate the vehicle. While accelerating it will take the command engine RPM will be higher but vehicle is not taking up the speed. Either it will stay to go at low speed or slowly it will starting to halt situation. This has happened few times(about 5-6 times). And in such situation there will some unacceptable noise from engine. One time we were at about 50mph speed but I couldn't accelerate (just like above) and had to stop the car in middle of highway, stop the car (shut the engine) and then start the car it started working fine. This happened mostly when on gas and especially during extreme cold weather. While on fully EV mode it works fine, I have never experienced this problem.

Filed Oct 8, 2020 · Acceleration, Brakes · GA · crash

Brakes when it wants to middle of traffic. Or braking assist will not kick in and engine jerks.

Filed Oct 7, 2020 · Acceleration · 16,660 miles · CA · crash

My car was in motion while preparing to park in an outdoor parking space at work only going 5 MPH or less. I turned my car slightly to the right since the parking space is at an angle when my car accelerated unexpectedly and I crashed into a fence and electrical pole. My brakes did not work and the air bags did not deploy. If it were not for the electrical pole my car would of run into a home. My car is currently at a honda dealership. The serviceman told me that no codes popped up when running a diagnostic test. They also took the car for a test drive and stated the car showed no issues. They are going to keep it overnight to test one more time. The man stated honda could not do anything unless a light came up on the dashboard.I do not feel safe in this car and I'm afraid this may happen again. Deciding of making a complaint to corporate.

Filed Apr 28, 2019 · Acceleration, Engine · 12,650 miles · CA

On approx 6 occasions, when EV power is used up, the car switches to ice mode with issues. When traveling up hill, it feels like the transmission is not engaging. The vehicle losses power, and does not accelerate. The ice revs extremely high without speed gain. Have also experienced a downhill situation with nearly full EV in EV mode. Vehicle feels like it disengages drivetrain. When pressing the accelerator, there was no response. One feels helpless when this occurs. Most of the time, the car had switches from EV to hv automatically, without issue. But, the above phenomena has happened 6 times in the last year this is unsafe. The vehicle was sold as an EV, with a gas engine to take over when EV runs out. At no time was there any explanation regarding potential situations that would cause the vehicle to become unsafe and lose power. One should not have to ensure reserve EV power for potential power loss situations. When these situations have occurred, upon shutting off the car and exiting, there is a strong smell of burning rubber and other material similar to transmission and brakes, or hot metal. Clearly something is overheating, and if the vehicle was not shutdown and allowed to cool, a reasonable person might conclude that significant damage to the engine, electric motors, EV battery, or transmission would take place. I am no longer driving the vehicle as a pure EV for city driving. The fear of power loss without control is extremely upsetting, and consequently, not getting the value of vehicle. My spouse will not drive the vehicle as driver or passenger if the trip is to exceed 20 miles in one direction. My gas savings has dropped considerably as I am unable to risk running out of EV before my trip ends. This vehicle has been taken to the dealer 3 times, and inspected by honda of america. They deny there is anything wrong with the vehicle.

Filed Apr 22, 2019 · Acceleration, Fuel system · 15,703 miles · TX

State of driving condition: the car was set in cruise at 70 MPH in hv mode (not charge mode). Ev range was 30 mile remaining, approximately 70% of battery remaining. The honda clarity phev spontaneous excessive revving the engine while cruising at a constant speed on flat highway road then the car dropped speed by itself without any car in front. Once I notice the car does not have power to regain to set cruising speed, I turned cruising off, switched the car from hv to EV then the engine stop doing high revving. I drove in EV for 2 minutes then switch back to hv then the car regain its power to resume cruising speed. This is a very dangerous situation when drivers did not aware when the car decided to cut its power in hv mode. This is the first time I encounter the situation, but I've noticed many similar complaints from other driver regard to clarity phev spontaneous engine revving on many forum.

Filed Feb 5, 2019 · Acceleration, Engine · 100 miles · NC

When vehicle is in any mode that require the internal combustion engine, it persistently gets stuck in a high rev, high RPM, state at any speed. This causes power fluctuations and extreme engine noise. This creates challenging and potentially unsafe driving conditions due to the sensitive state of the engine when stuck in this mode.

Filed Nov 2, 2018 · Acceleration · 3,000 miles · CT · crash

Vehicle was in a parking garage, when making a right turn at the top of a ramp traveling at about 5 MPH, the vehicle went into max acceleration. There was no braking effect when the brakes were applied. After a little over a hundred feet the vehicle crashed into 2 parked cars which were totaled also. The car had crash mitigation but it did not appear to activate. The airbags deployed so the driver had only minor injuries. Hopefully an analysis of the black box will enable honda to fix this problem.

Filed Aug 9, 2018 · Acceleration, Airbags · 1,100 miles · PA · crash · 1 injury

Tl* the contact owned a 2018 honda clarity plug-in hybrid. While driving 30 MPH and making a right turn into a parking lot, the vehicle accelerated independently without warning. The steering wheel seized and the contact crashed into a store. The front driver and passenger air bags failed to deploy. The contact sustained shoulder and collarbone injuries that required medical attention. The front passenger did not sustain injuries. A police report was filed. The vehicle was towed to a tow lot. The vehicle was not taken to a dealer or an independent mechanic for diagnostic testing. The vehicle was destroyed. The manufacturer was not notified of the failure. The approximate failure mileage was 1,100. The VIN was not available.