Adaptive Cruise Control problems of the 2018 Honda Accord - part 1

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.

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.

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.

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.

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.

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.

- 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.

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.

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.

While driving in a busy area with pedestrians and other vehicles, my car hard braked out of nowhere to a complete stop for no reason. I was nearly rear ended. The adaptive cruise control shuts off completely after 15 minutes in use. Says to take it to the nearest dealership. Turning off and restarting the car gets rid of the notification.

Experiencing an ongoing issue where multiple warning lights appear on the dashboard at the same time. The lights include several safety and system warnings, making it look like many different systems in the vehicle are malfunctioning simultaneously. Even after repairs were made, the dashboard warning lights continue to stay on or return shortly after. It has become frustrating because the vehicle continues to show problems even when something has already been fixed. This is a safety concern. How can we know if something is actually malfunctioning if codes are being thrown, constantly?? we also can’t use the safety features included with the vehicle when this is happening. Having so many warning lights on at once also creates concern about the reliability and safety of the vehicle, especially since several of the warnings relate to important systems such as braking, driver assistance features, and engine performance. Repairs aren’t helping and I’m seeing sooooo many other 2018 Accord owners with the same issue, as has been documented with this site, NHTSA.

The car will have all lights on dashboard showing, car has been taken multiple times to dealership and nothing seems to be wrong but this cause all safety features to malfunction. I have talked with other Honda owners, on forums and acquaintances and they have similar issues.

The warning lights for many areas has come on without warning. The car runs and drives fine. Took it to Honda. They want between 500 - 2500 to resolve the issue and replace the front radar. This appears to be a consistent problem for these 2018 Hondas. I already had to have the fuel injectors replaced at 48k miles. Another common Honda problem. Please help us as consumers.

These also are warning signals that keep coming on I took it to autozone obd scanner said is was misfire cylinder2got spark plug changed and engine coil still showing same thing on scanner.

When it is cold outside my acc light comes on and when I started my car the other day it read emissons service problem avoid heavy acceleration and high speed. That was just 1 among 7 other service warning that popped up.

My car is having the head gasket issue which caused an issue while driving.

Advanced driver assistance systems (adas) this has been ongoing since I had the car and have taken to dear ship several times and they say it to happen, so they get the messages and the messages are there. I look it on google and there have several complaints about this issue and I have Honda and they are very rude about it, I have even call here and the young pay no mine what soever told me to call Honda I need mt=y problem resolve please, I am scared to drive my out state , I am [xxx] and live in north carolina and these people cannot drive. I have pictures which I sent as attachments. Somebody please help me. My payments' are 655. 00 a month and need to fill safe driving this vehicle information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

Head gasket blown on a 2018 Honda Accord 1. 5 turbo. Yes, yes warning lights have appeared.

I had been driving down highway and all of a sudden my car put on brakes hard. Thank goodness no one was behind me. I had dealer turn off that feature so it wouldn't happen again. I still experience my brake light flashing when nothing in road to brake for but doesn't brake on its own. Issue having now is issues starting car and once it starts I recieved a collision mediations issue pop-up on display saying see dealer now. Cruise control issue, and on dash has traction control saying ignitionating continue driving. The braking issue started right after purchase in 2018. The starting issue started yesterday 7/25/2025.

I was behind another vehicle with the adaptive cruise control on and been following the for some distance at a speed below the cruise control setting. Warning came on for the braking mitigation, cruise control disengaged, vehicle began coasting but did not brake. I continued home driving without any other changes, but warning stayed on. After arriving turned vehicle off and restarted, warning did not come back on. I have not driven vehicle since. I checked and found other reports of similar problems and am filing this report. Will continue driving with extra caution and report any other occurrences.

Unknown.

Car goes in limp mode once the brake system lights come on. When the brake light system comes on, none of the functions for the automatic breaks or electrical portion of my vehicle works. The car will act as if it will not accelerate right before the codes start to appear on the car.

This is about the 5th time this has happened to the car. All warning lights appeared spontaneously while driving. The lights would turn off if the car was turned off for a long period of time or is we disconnected battery for a long period of time. We have tried to research the problem and no one seems to know what the cause or permanent fix is.

The vehicle was totally inoperable and suddenly came to stop was lucky that was driving in a local road where there was no vehicle, suddenly all different warning signs were coming on the dashboard and couldnt drive at all and vehicle was totally stalled. It was very dangerous situation luckliy I was just came off a very busy road otherwise coudl have been major incident. Currently the vehicle is at dealership nto sure what they will say but just wanted to report this as it is very dangerous situation.

If car is idling for over 1 minute, all lights on dash come on. When all lights on, car wont wont go over mph, car will randomly sputter in highway when going over 1rpm and will stall randomly. Reported on reddit by multiple people and when I went in to get it diagnosed it was the fuel injector issue.

• head gasket • none of the safety features work when there is a head gasket issue. Power steering is reduced as well as break performance • confirmed by Honda dealership with a boroscope • Honda • no warning, Honda at first thought it would be fixed by fixing the factory recalls. Light went away prior to taking it in and then looked in to it 2 weeks later and diagnosed head gasket failure.

While driving on the interstate, suddenly got 6 different ‘warning’ messages on the dashboard. Most of them involved the brakes. Emergency brake malfunction, brake hold malfunction, forward collision malfunction, adaptive cruise control malfunction, brake system malfunction (use of brakes may be reduced), and road departure mitigation malfunction.

The car is braking even when there is no obstacle or vehicle ahead. I have not driven at higher speed but I fear that if that happens, it can cause incident and injury.

All dash lights are on and the Honda dealership told me I have a blown head gasket, need a turbo replacement & fuel pump in which I wasn’t able to drive the car for 7 months at 112,276 miles. . This seems like a known issue for this make and model vehicle after 100,000 miles.

I recently took my car to the dealer because I have multiple messages on my dashboard saying please see dealer dealing with my brake system, electric power steering, vehicle ability assist, collision mitigation system problem, etc the dealers don’t know what’s going on with it. I recently had service done on it because of the recall with the fuel pump and even before that those messages were showing up.

Gasket headed.

Adaptive cruise control - collision mitigation - road departure mitigation - vehicle stability assist - hill start assist - electric parking brake - tire pressure monitoring.

Getting a dash warning that all mitigation systems are not working and to see my dealership.

Everyday the vehicles struggles to pick up on speed and stalls out. I am often holding up traffic because I’m driving to slow. I have to very very very slowly accelerate so that the car doesn’t stall. When the trying to accelerate it often skips and jerks while driving. I often wonder if this will affect me while driving on the interstate. I fear that a bad accident is on the horizon with these issues. Could you please help. I’ve tried multiple times since last December to get the car fixed and Honda refuses to fix my vehicle even though I received a letter in the mail saying more repair parts are available.

During normal driving - clear weather conditions - the car will suddenly activate the forward collision braking. It will literally slam on the brakes and decrease the speed by 10-15 mph. This happened as I was going down the drive of our neighborhood, I was at 45 mph with no one in front of me or behind me (thankfully) and the car applied the brakes and activated the front collision warning. There is also an intermittent issue with my seatbelt. Specifically the drivers seat belt. I was witness to someone driving my car - he buckled his seat belt and it unlatched. He then buckled it again thinking he didn’t do it right - but it wouldn’t latch. This has happened to me before as well - but usually after the third try of buckling the seat belt it will work and so I thought nothing of it. Additionally, the windshield wipers do not go back to their original position after being in use.