2018 Honda Accord Driver assistance Problems

I am reporting a recurring safety and mechanical issue with my 2018 Honda Accord 1.5T, which currently has approximately 128,900 miles. My vehicle has been experiencing shaking/rough operation and multiple warning lights while driving. Diagnostic scans have shown P0301 – Cylinder 1 Misfire and U0401-68. The ignition coils were replaced with original/OEM parts in an attempt to correct the issue. After the repair, the warning lights went away temporarily, but within several days the same warning lights and symptoms returned, and the vehicle again showed the P0301 cylinder 1 misfire code. I am concerned because the vehicle continues to shake and operate abnormally despite the repair. I have learned that Honda has addressed cylinder-head-gasket concerns involving certain 1.5L turbocharged Accord vehicles, which may cause engine misfires. However, I have not had my vehicle diagnosed with a defective head gasket, so I am not claiming that this is definitely the cause of my vehicle's problem. When I checked my VIN through NHTSA, it showed 0 unrepaired recalls. I am submitting this complaint so that NHTSA has a record of the recurring problem and can determine whether my vehicle's condition may be related to a broader safety defect affecting 2018 Honda Accord 1.5T vehicles. I am concerned about the possibility of the continued misfire causing loss of engine performance, loss of power, stalling, or otherwise making the vehicle unsafe to operate if the underlying problem worsens. I have photographs of the diagnostic scans documenting the codes and records showing the previous repair.

NHTSA ID

11764229

Incident

Sep 2, 2026

Since I purchased this car in 2022, the collision mitigation braking system has randomly engaged for no reason. This has happened multiple times over the years, day and night, when no other vehicle, road obstructions, or other factors warrant the system triggering.

NHTSA ID

11763757

Incident

Sep 11, 2026

I own a 2018 Honda Accord Sport 2.0T that has been consistently maintained through authorized Honda dealerships. On July 30, 2026, at 135,968 miles, I took my vehicle to Nalley Honda for a Blind Spot Information System warning and maintenance. The dealership performed a multi-point inspection and documented the spark plugs, cooling-system hoses, and fluid leaks as PASSING. I authorized approximately $1,231 in repairs and maintenance. Only days and approximately 202 miles later, multiple warning lights appeared. I returned to the same dealership. At 136,170 miles, Honda documented DTC P0302 (Cylinder #2 Misfire). The injectors passed an air-fuel test. The technician then noted pressure releasing from the cooling system despite low coolant temperature. A head-gasket leak test was performed and FAILED. Honda diagnosed a blown cylinder head gasket and recommended approximately $4,906 in repairs, including spark plugs that had passed inspection only days earlier. I am concerned about the sudden failure of a major engine component in a well-maintained vehicle, particularly so soon after a Honda dealership inspection. I have learned that other Honda Accord 2.0T owners have reported premature head-gasket failures. A failed head gasket can result in misfires, coolant loss, overheating, reduced engine performance, and potential engine damage while driving. I am requesting that NHTSA review this complaint along with similar complaints involving Honda Accord 2.0T head-gasket failures to determine whether a defect trend exists and whether an investigation is warranted.

NHTSA ID

11761480

Incident

Aug 3, 2026

On August 29th 2026 at 1:28PM (13:28) 148,320 mi. on odometer During interstate driving and topping the Sunshine Skyway Bridge on Interstate 275 Northbound (27.617863, -82.653639) the vehicle detected both road departure and engaged the emergency automated braking due to the shadow generated by the superstructure of the Skyway Bridge falling on the road surface. The vehicle attempted to correct the "road departure" by steering the vehicle away from the perceived problem and violently engaged the brakes nearly causing a collision as it has done numerous times before. In this particular event, it was an extraordinarily dangerous situation given the location that it occurred (190ft in the air on a walled in 2 lane interstate highway). I have reported this to NHTSA and American Honda on multiple previous occasions and await a repair or even an acknowledgement of this extremely dangerous issue. Honda has opened a case on this but have had 12+ months and no response has been issued.

NHTSA ID

11760916

Incident

Aug 29, 2026

I purchased my 2018 Honda Accord Sport from CarMax on January 16, 2026, and I have had several serious problems with the vehicle since purchasing it. Every warning light on the dashboard has come on, my radar system will not stay calibrated, and I have been told that my fuel injectors need to be replaced. In addition, the relay module was already broken when I received the vehicle, which causes the interior lights in my car not to work properly. These issues have caused serious concerns about my safety and the safety of others because I cannot depend on the vehicle’s safety systems or know when another component may fail. The vehicle and affected components are available for inspection upon request. I have attempted to get these problems addressed, but I have not been able to get a satisfactory resolution. The issues have been identified/diagnosed, and I am seeking further inspection to determine the full extent of the problems. I have not had the vehicle inspected by the police or an insurance representative, but I am trying to get the manufacturer/dealer involved so these issues can be properly documented and addressed. I am especially concerned because I have only had this vehicle since January 16, 2026, and I have already put a significant amount of money into it while still owing a substantial amount on the loan. I was also informed that the vehicle could potentially be considered a total loss within the next couple of months. I do not believe it is reasonable for me to be left responsible for a vehicle that I recently purchased from CarMax and that has developed or revealed so many serious problems. I am requesting assistance in determining whether these issues can be properly repaired, whether the vehicle is safe and reliable to drive, and what options are available to me for a resolution given the amount of money I have already invested and the remaining balance on my vehicle loan.

NHTSA ID

11760217

Incident

Feb 20, 2026

Issue 1: Faulty Collision Mitigation Braking System & Subsequent Crash Incident Details: In July of 2025, my vehicle’s automatic braking warning lights randomly activated and triggered an unprompted, emergency stop on [XXX]—despite having no vehicles ahead of me. This sudden malfunction directly caused a rear-end collision on the interstate. Documentation: A formal crash report was filed with the Georgia State Patrol. Ongoing Risk: The false automatic braking warnings continue to trigger randomly, creating an extreme safety hazard for myself and surrounding traffic. Issue 2: Premature Turbocharger Failure & Cracked Head Gasket Diagnostic Timeline: Immediately upon picking up the car from a body shop repair, every warning light on the dashboard illuminated erratically. After Ed Voyles Honda in Marietta claimed nothing was wrong, the body shop replaced a potentially loose battery cable. The issue persisted, and Shottenkirk Honda in Cartersville ultimately diagnosed a total turbocharger failure in March 2026. Out-of-Pocket Cost: Honda denied any goodwill coverage despite the widespread, documented failure of these 1.5L engines across 2018–2023 models. I paid $1,700 out of pocket to replace the turbocharger. Escalating Failures: Shortly after the turbo replacement, the head gasket cover cracked—another notorious, widely recognized defect inherent to this specific engine setup. At only seven years old, this vehicle has proven to be unreliable, dangerous, and financially burdensome. The known defects in the 1.5L powertrain warrant a widespread recall. Given my long-standing loyalty and the severe nature of these defects, I request a full reimbursement of the $1,700 turbocharger repair costs and an immediate investigation into the phantom braking issue. I expect a prompt reply outlining how Honda intends to resolve these safety issues. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11758960

Incident

Jul 29, 2025

These 9 things are on my dashboard- I’ve called Honda corporate to see if they could do something about this because I’m not the only one with this problem. My car is now barely drivable and the dash have not went away Emission system Road departure mitigation system Brake system problem Collision mitigation braking system Hill start assist problem Adaptive cruise control system Vehicle stability assist system problem Electric power steering system

NHTSA ID

11758438

Incident

Jul 15, 2026

While driving my 2018 Honda Accord Sport 1.5T, multiple warning lights suddenly illuminated on the dashboard at the same time and several warning messages appeared. The vehicle displayed warnings for different systems, including a message stating, “Hill Start Assist Problem. Vehicle May Roll Upon Brake Release. See Your Dealer,” along with the check-engine light and several other warning indicators. I purchased this vehicle brand new in 2018, and since the day I purchased it, I have consistently had the vehicle serviced and maintained at an authorized Honda dealership. I have relied on Honda to perform the recommended maintenance and address any problems with the vehicle. When all of these warning lights and messages appeared, I took the vehicle to the Honda dealership. The dealership adjusted the valves and told me that everything was fine. Approximately one week later, I had to take the vehicle back because the problem was not resolved. At that time, I was told that the vehicle needed a head gasket. The vehicle had also previously required a turbo replacement. Because of the seriousness of the head-gasket diagnosis, I obtained a second opinion from another repair facility, and they also determined that the head gasket was the problem. I do not understand how a vehicle that I purchased new and have consistently maintained through Honda could experience these significant engine-related problems. I am especially concerned that numerous unrelated warning lights and safety-system messages appeared simultaneously before the head-gasket problem was diagnosed. I am submitting this complaint because I believe this issue should be investigated to determine whether other 2018 Honda Accord 1.5T vehicles are experiencing similar head-gasket, turbo, and multiple-warning-system problems and whether these failures may represent a defect that should be addressed by Honda or through a recall.

NHTSA ID

11757957

Incident

Mar 25, 2026

While driving, the vehicle suddenly jerks or “jumps,” followed immediately by a noticeable loss of power. Shortly after this occurs, the multi-information display shows a series of warnings that include: Collision Mitigation Braking System Problem – See Your Dealer Adaptive Cruise Control System Problem – See Your Dealer Road Departure Mitigation System Problem – See Your Dealer Auto High-Beam Problem – Manual Controls Available – See Your Dealer Brake System warning light A “Systems Initializing… Continue Driving” message also appears. I have photographic documentation of these dashboard messages. This sequence creates a significant safety concern. The sudden jerk and power loss can occur while the vehicle is in motion, and the subsequent disabling of the Honda Sensing systems (Collision Mitigation Braking, Adaptive Cruise Control, and Road Departure Mitigation) leaves the vehicle without those critical driver-assistance features. Because this involves sudden power loss and the disabling of safety systems, I consider the issue urgent and ask that it be prioritized.

NHTSA ID

11757220

Incident

Aug 12, 2026

The head gasket is failing and causing the engine to overheat and misfire. Its a repeating issue I see online and have taken it to a certified Honda mechanic multiple times. The first diagnosis stated that the biggest issue was the fuel injections. Now this second diagnosis shows the head gasket. It poses a great danger especially in highways, as it causes the car to decelerate on its own and rattles as if it's losing power. It will overheat when it is idling. The check engine light turned on a week after purchasing the car from a local dealership, and the dashboard lights were wiped from the system prior to buying the car a year ago. Now I'm looking at over 7k in repairment costs while still financing a car I believed was reliable.

NHTSA ID

11757068

Incident

Sep 4, 2024

The dashboard lights up”brake” and the car slams on the brakes unexpectedly on occasion- and sometimes for no known reason. This has happened countless times. yesterday it happened again while driving on the intersection at 70 mph . there were no vehicles in front of me and I was not changing lanes, but the car slammed on the brakes, making the car behind me almost rear-ended me & cars having to swerve around my vehicle. This is very unsafe and it needs to be addressed and corrected by Honda.

NHTSA ID

11756912

Incident

Aug 13, 2026

I am reporting a safety concern involving my 2018 Honda Accord. I purchased my vehicle used in January 2024 at approximately 90,000 miles and have kept up with the recommended maintenance during my ownership. At approximately 120,000 miles, a Honda dealership diagnosed head-gasket failure with coolant intrusion involving cylinders 3 and 4. Before diagnosis, the vehicle experienced rising engine temperature while idling, coolant loss, jerking during acceleration, numerous warning lights, and severely reduced acceleration. The problem progressed to loss of power and stalling while driving and slowing/stopping, requiring me to place the vehicle in Park and restart the engine to continue driving. The vehicle also developed unstable RPMs and engine surging while in Park. Honda performed a cooling-system pressure test and borescope inspection and confirmed coolant intrusion. Head-gasket replacement cost approximately $5,000. I contacted American Honda (Case #16533411), but goodwill assistance was denied because the vehicle is outside warranty and Honda stated it had no Honda-dealership service history. I am reporting this because the head-gasket failure resulted in loss of propulsion and stalling while operating the vehicle, creating a serious safety concern.

NHTSA ID

11756560

Incident

Aug 1, 2026

While driving, my vehicle began shaking/rough running and the check-engine light came on. Multiple warning lights and system warnings appeared on the dashboard, including the brake system, steering, traction control, and TPMS warnings. The vehicle experienced noticeable shaking and reduced/abnormal performance. I am concerned that this may be a safety-related defect because multiple vehicle systems are being affected.

NHTSA ID

11756096

Incident

Aug 10, 2026

The contact owns a 2018 Honda Accord. The contact stated that upon starting the vehicle, the engine and TPMS warning lights illuminated. The message that the vehicle should not be driven was displayed. The lane assist feature was inoperable. The contact disconnected the battery, and the warning light disappeared. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 55,000.

NHTSA ID

11753272

Incident

Jul 17, 2026

Mileage

55,000 mi

The Acoustic Vehicle Alert System (AVAS) stopped emitting sound for no apparent reason. On June 2nd, I took it to Honda service center, they said the speaker behind the front bumper needed to be replaced. I paid $699.56, only to discover that the AVAS still didn't work. I took it back, they said the accoustic unit needed to be replaced. I paid $707.57. On June 18th, they called me to pick up the car; I asked if the sound was working, they said the sound was there but it wasn't as audible as in other comparable cars. When I drove the car, I found a parking lot and drove below to 25 miles, even when the car was put in EV mode, I personally could not hear any noticeable sound even with the window open. I had contacted American Honda, and reported the issue, especially that the service centers didn't seem to know how to fix the issue. I requested from American Honda that they dispatch an egineer or provide the Honda service centers with directiond how to fix. Nothing happened. I'm not convinced that the AVAS was fixed. The design is faulty and many cars risk to be grounded because of that. The worse part was that the Honda service centers are not able to fix the issue. I just wasted $1,407.13 (plus the Uber rides) for nothing. Also, I don't understand why they held the car from June 2 until June 18th, and when I asked about the status, no meaningful update was given. This issue is likely to occur again with thounsands of hybrid cars.

NHTSA ID

11751174

Incident

May 26, 2026

ALL WARNING LIGHTS FLAS ON DASHBOARD CONTINUOUSLY

NHTSA ID

11747374

Incident

Jun 26, 2026

There are 13 alerts showing on the instrument panel for various systems not functioning, along with accompanying yellow dash lights such as tire pressure, ABS, brake system, traction control, ACC, and LKAS. Systems not available include, ABS system, Adaptive Cruise Control, Road Departure Mitigation, Auto High-Beam, TPMS, Electric Power Steering, plus several others. These alerts first started January 2026 and occasionally would disappear; however, over the past few months the warnings have become constant. The vehicle has approx. 120,000 miles. Due to TPMS not functioning, I am not given a warning when a tire has gone flat/blown while driving as the tire pressure light is always on the dash. The only warning I am provided is the sound/smell of the rim dragging along the road to notify me the tire is flat. This poses a risk to myself and others by creating an emergent situation requiring me to pull over rapidly. Another incident occurred when ACC was enabled (at a time when the alerts had been appearing on and off). Cruise control set at 70 mph when suddenly the above mentioned alerts reappeared and ACC system became unavailable, leading to unexpected deceleration on the highway. This poses a risk to myself and others as it creates unpredictable driving patterns, unbeknownst to the driver. Initially I replaced the battery with no resolution of the issue. I later discovered maintenance code displayed by the vehicle was C003A-62 for Right Rear Wheel Speed Sensor Circuit Failure (circuit short to ground or open). The mechanic recommended replacing the right wheel hub assembly as this was suspected to be the cause of failed circuit. When that repair lasted no more than 10 mins before the warnings reappeared, the right rear wheel speed sensor itself was then replaced. Similarly, this did not fix the issue. I have not sought additional service due to repair costs beginning to add up with no resolution. Based on the history of reports, this issue does not seem uncommon.

NHTSA ID

11746593

Incident

Jun 25, 2026

Yas

NHTSA ID

11746064

Incident

Jun 11, 2026

I am writing to formally lodge a complaint regarding a recurring issue I have experienced with the head gasket in my vehicle. I have owned several vehicles of this make and model, and I have observed a troubling pattern of blown head gaskets that has not been adequately addressed. Specifically, my current vehicle has suffered from this problem, resulting in significant inconvenience and additional repair costs. This issue appears to be prevalent across this year model as well, suggesting a potential design flaw or manufacturing defect that warrants further investigation. I respectfully someone to look into this matter to determine if a broader safety concern exists that needs to be addressed. Owners of vehicles affected by this issue may be at risk of serious engine damage and costly repairs. Thank you for your attention to this important issue. I look forward to your response.

NHTSA ID

11742594

Incident

Mar 16, 2026

The contact owns a 2018 Honda Accord. The contact stated that while driving at 45 MPH with the cruise control engaged, the brakes suddenly applied without application. The brake message was displayed. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not notified about the failure. The approximate failure mileage was 99,735.

NHTSA ID

11741243

Incident

Jun 1, 2026

Mileage

99,735 mi

Vehicle: 2018 Honda Accord On [XXX], at approximately [XXX] PM, I was driving on [XXX] [XXX] at approximately 35 mph. The weather was clear and the road was dry. A vehicle ahead of me began turning into [XXX] N. My vehicle’s Collision Mitigation Braking System / automatic emergency braking system activated suddenly. The system made an audible warning sound, displayed a warning icon, and applied braking even though I did not believe there was a crash-imminent situation. There were vehicles behind me at the time, so the unexpected braking created a potential rear-end collision risk. The braking event also caused back pain, and I later experienced some stomach discomfort. I am concerned this was a false activation of the automatic emergency braking / Collision Mitigation Braking System. I am also concerned because the system reactivates after the vehicle is restarted, meaning I cannot reliably prevent another unexpected braking event from occurring. I am requesting that this be documented as a vehicle safety concern involving possible false activation of the automatic emergency braking system. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11739724

Incident

May 23, 2026

While driving vehicle detected both road departure and engaged the emergency automated braking. The vehicle attempted to correct the "road departure" by steering the vehicle away from the perceived problem and engaged the brakes nearly causing a collision as it has done numerous times before. I have reported this to NHTSA and American Honda multiple times and await a repair of this dangerous issue. Honda has opened a case on this but have had 18 months and no response has been issued.

NHTSA ID

11739622

Incident

May 14, 2026

- the car's automated systems randomly applies severe breaking at improper times - the cars head gasket has blown and in turn has blown the radiator and thermostat

NHTSA ID

11738708

Incident

May 16, 2026

All lights on head dash are on , all components are not working properly or effected because of this. (Engine light brake light abs light tire light traction control light , sensors out all) while driving vechile reduces power does not operate randomly , have to pull over shut the car off and turn it back on. Has high vibrations lot of shaking, stauling. I have had it looked at with multiple shops and dealer . Everybody is playing a guessing game and can not pin point what exactly it is . Was told it was spark plugs and coils, alternator , fuel injectors. ALL have been repaired, and still have all lights on dash and still facing every problem listed after repairs. Been inspected by manufacturer. Say not been resolved was told if it wasn’t what was already fixed they don’t know and that this is very common right now . It first APRIL 2026 (3) times. May 2 times 2026

NHTSA ID

11735520

Incident

May 2, 2026

The day I purchased the vehicle from the dealer, every warning light began cycling on including the automatic emergency braking failure, engine system failure and others. I immediately took the car back to the dealer and they supposedly repaired it. When the car was returned to me, I drove it for less than a week and the same thing happened again. When the light came on, the car’s auto braking and cruise control stopped working. I took it back to the dealer and they said it was the head gaskets, which they fixed. When I got the car back again, I drove it for 2 days and it did the same thing again, this time all of the warning codes came on. This time, I had a total engine failure because the timing chain broke. The dealer took almost two months to replace the engine and it cost us almost $6,000. I got the car back last Saturday. Today, driving home from work, the automatic brake system failure warning came on again and the car won’t automatically brake and cruise control wouldn’t work. This is exactly what happened last time. I am afraid to drive this car because I don’t know if the brakes will fail and the system currently isn’t working. We are taking it back to the dealer which will likely cost us more money. We are stuck with this car and cannot get rid of it because we owe more money on it then it is worth because of replacing the engine.

NHTSA ID

11734702

Incident

Apr 29, 2026