2015 Honda Odyssey engine problems

ENGINE

I first experienced an engine misfire in February 2025. The vehicle had a P0301 misfire code, and at the time I was unaware of Honda’s extended warranty related to this issue. We had a trusted mechanic friend inspect the vehicle and replace the spark plugs and ignition coils. He noted that there was significant carbon buildup. After those repairs, the vehicle appeared to run normally, and we believed the issue had been resolved. Later, I received Honda’s extended warranty notice and realized that the issue I experienced may have been related to the condition covered by the warranty. I contacted my local Honda dealership in August 2025 and explained the prior misfire, repairs performed, and the warranty notice I had received. However, because the check engine light was not currently illuminated, I was told there was nothing that could be done unless the vehicle was actively displaying the issue. I also contacted Honda Corporate regarding this matter. I was advised that reimbursement for some of the repairs I had already completed might be possible, but that it would need to be reviewed. I chose not to submit those receipts at the time because I was concerned that doing so might impact my ability to use the extended warranty coverage if the problem returned. Unfortunately, the issue appears to be progressing. On June 2, 2026, the vehicle set a P3400 code, which is related to the Variable Cylinder Management (VCM) system. At that time, the oil level was low. After adding oil and completing several driving cycles, the check engine light turned off. However, the vehicle continues to consume oil at an alarming rate. I have had to add additional oil again in July. The problem is progressing - it is the issue that should be covered by warranty but holds refuses to do anything because the light isn’t currently on,

NHTSA complaint #11753638 — an unverified report by a vehicle owner.

ENGINE

American Honda Motor Co., Inc. issued an official Warranty Extension in July 2025 covering engine misfires from piston ring deterioration (DTCs P0301-P0304) on 2013-15 Pilot and 2013-17 Odyssey vehicles. My 2015 Honda Odyssey (VIN: [XXX]) experienced this exact defect, resulting in severe engine misfires and secondary alternator failure caused directly by engine fluid saturation leaking onto it from the primary defect. I paid $5,275.80 for repairs prior to campaign awareness (Invoices XXX and XXX). I submitted complete reimbursement documentation on January 31, 2026. Honda has withheld my funds for 178 days (which is 122 days past their promised 8 week deadline) while corporate customer care agents falsely claim payment is “approved but pending final management sign- off.” I have called 11 times and corporate managers who are never available HAVE NEVER returned my calls like the representative with Honda I've spoken with each time assures. This deliberate delay subverts federal safety campaign integrity and artificially manages liability exposure. Request immediate enforcement action for an ongoing corporate warranty evasion pattern. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11753339 — an unverified report by a vehicle owner.

ENGINE

I had an engine failure on my odyssey that was causing a single piston to misfire - that i then had a honda dealer repair for around $3500. A couple months later i received a letter indicating this specific type of error was now under a recall for my vehicle so i submitted all the documentation for the recall reimbursement. That was in August of 2025 and I have still not received reimbursement - each time I contact Honda i am told this is just the normal process but nobody is able to provide me a date of when it will be reimbursed.

NHTSA complaint #11738121 — an unverified report by a vehicle owner.

ENGINE

I bought this car from a dealer in November of 2025 just over 95k miles. Two weeks after I bought it a PO303 code for a cylinder 3 misfire appeared. I changed the spark plug and the code went away. Then on Friday, April 10th, the code came back. I replaced the spark plug for a 2nd time. The code disappeared again. Then, on April 25th the code returned and I replaced the cylinder 3 spark plug for the 3rd time. After replacing the cylinder 3 plug for the 3rd time I took the car to an auto mechanic in my area. After their diagnosis I am looking at either repairing the current engine at a cost of 4500 dollars or replacing the engine at a cost of 7-8k. I believe my engine issue is the very same issue that 2011-2013 3.5l v6 Honda engines suffer from that resulted in a lawsuit and settlement.

NHTSA complaint #11735195 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2015 Honda Odyssey. The contact stated that while driving at various speeds, the vehicle would hesitate to accelerate as intended while the accelerator pedal was depressed. The check engine warning light illuminated. The vehicle was towed to a local dealer, where it was diagnosed with a piston ring failure and related the failure to Honda Service Bulletin:25-061. The vehicle was not repaired due to cost. The manufacturer was made aware of the failure. The failure mileage was approximately 160,000.

NHTSA complaint #11734872 — an unverified report by a vehicle owner.

ENGINE

Our 2015 Honda Odyssey van has bad piston rings 1-3. The check engine light and all of the lights are on in the vehicle is not driving and idling poorly.This is the second time it has happened. The first time was under warranty at 112,000 miles, and now the van has 179,000 miles. There seems to be several recalls and known problems and warranty was extended last year, but we just missed it. The code is P0301. I took it to the Honda service and the spark plugs are fouled.

NHTSA complaint #11733880 — an unverified report by a vehicle owner.

ENGINE

In November 2024, the engine of my 2015 Honda Odyssey misfired and I had all spark plugs replaced. The vehicle had 102, 171 miles on it. The issue was resolved at that time. On April 1, 2026 the engine misfire returned, check engine light came on and the repair shop advised that again the engine is having the same issue. The vehicle now has 117,000 miles on it. This does not appear to be an isolated case as I have read several other similar complaints.

NHTSA complaint #11729019 — an unverified report by a vehicle owner.

ENGINE

Approximately 7 months ago, my 2015 Honda Odyssey experienced an engine misfire with code P0302 (cylinder 2). All spark plugs were replaced at that time and the issue appeared resolved. However, the misfire has now returned with the check engine light on, again indicating cylinder misfire. The vehicle only has 71,000 miles on it, which makes this recurring issue particularly concerning. Based on my research, this appears to be a known defect related to Honda’s Variable Cylinder Management (VCM) system causing excessive oil consumption and spark plug fouling — an issue documented across 2013–2017 Odyssey vehicles and addressed under Honda Service Bulletin 25-061. I am requesting this complaint be on record and urge NHTSA to investigate this as a safety-related defect.”

NHTSA complaint #11727615 — an unverified report by a vehicle owner.

ENGINE

Honda issued a warranty extension covering piston ring deterioration that causes engine misfires (DTCs P0301–P0304) due to oil fouling. I experienced this exact condition on 3/11/25 prior to issuance of the warranty extension, resulting in an engine misfire and loss of drivability. To restore basic operation of the vehicle, an independent repair facility replaced a fouled spark plug, documenting the misfire and oil fouling condition (including the P0301 code). I elected the minimum necessary repair to restore drivability, as the warranty extension had not yet been issued and the vehicle could not be operated safely without immediate service. Honda has acknowledged that this repair was temporary and consistent with the covered condition. Honda has denied reimbursement for this repair because the piston ring or short block replacement identified in the campaign was not completed. Honda has also stated that it will not perform the covered repair unless the misfire code is currently active or stored and the check engine light is illuminated. Honda representatives have acknowledged that this condition commonly recurs after a temporary spark plug repair, but have advised that no repair can be performed unless the issue resumes. This creates a situation in which the vehicle has a known covered defect, but access to repair is delayed until failure reoccurs, potentially outside the warranty extension mileage or time limits. I am submitting this complaint due to concerns that these requirements may prevent timely access to emissions-related repairs for a known defect and may discourage reasonable interim repairs necessary to maintain safe vehicle operation. Honda’s requirement that I continue operating the vehicle until the misfire reoccurs raises safety concerns. The prior failure resulted in loss of drivability, and I am uncomfortable transporting my family while knowingly operating a vehicle with a documented defect that Honda has acknowledged is likely to recur.

NHTSA complaint #11716004 — an unverified report by a vehicle owner.

ENGINE

American Honda Motor Co, Inc. recently sent a warranty extension due to piston ring deterioration causing misfires. They have improperly denied my claim for reasons that were clearly arbitrary and to get out of reimbursing me for the repair. This is a safety concern because the car is unable to accelerate safely to merge onto an interstate and puts other drivers at risk.

NHTSA complaint #11691143 — an unverified report by a vehicle owner.

ENGINE

had purchased my 2015 Honda Odyssey in the year of 2015. When I first went in for a first service my car have a light saying Check engine, check VSA, check LDW, check FDW and once a while my shake when we are on the road. We told the service people at the dealership to have a look at it but they said nothing wrong with it.

NHTSA complaint #11689949 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2015 Honda Odyssey. The contact stated that while driving at night, the check engine warning light started flashing. The contact was able to pull over. The contact called a mobile mechanic who determined that there was a misfire in cylinder #1, and that the spark plugs needed to be replaced. The spark plugs were replaced, but additional repairs were needed. The vehicle was taken to the local dealer where it was diagnosed and determined that the spark plugs, and piston rings needed to be replaced. The vehicle was repaired. The manufacturer was contacted and determined that there was no warranty coverage for the failure, and no assistance was provided. The approximate failure mileage was 92,000.

NHTSA complaint #11682473 — an unverified report by a vehicle owner.

ENGINE

I am reporting an engine defect covered under Honda’s recent warranty extension for 2013–2017 Odyssey / 2013–2015 Pilot vehicles when the MIL comes on with DTCs P0301–P0304. On November 1, 2022, I was stranded on the road when the check-engine light came on. At Honda Muller of Gurnee, the dealer diagnosed misfires consistent with P0301–P0304, explaining the underlying cause as piston ring function deterioration with sludge causing oil to foul the spark plugs. I was told my original warranty had expired only about six weeks earlier (on August 29, 2022). Coverage was denied and I was quoted over $6,000. Because I couldn’t afford the repair, the dealer recommended replacing the spark plugs as a temporary measure only, stating this would not fix the underlying defect. I proceeded with that temporary measure. On November 11, 2022, American Honda formally acknowledged my concern in writing, confirming that Case #13455791 had been opened and escalated to a case manager in direct response to my diagnosis from November 1, 2022. Despite this acknowledgment, my repair request was denied. In 2025 I received Honda’s warranty extension letter acknowledging coverage for this exact defect (including coverage through January 31, 2026). I returned to the dealer seeking repair based on my documented diagnosis, but repair was refused again because the codes were not present that day (the condition is intermittent). This defect affects drivability and safety (loss of power/hesitation and reduced ability to merge or cross traffic). I am asking NHTSA to record this complaint and consider action so that owners with documented prior diagnoses — especially those recognized by Honda corporate — are not refused repairs simply because an intermittent defect isn’t active at the exact moment of inspection. I am reporting an engine defect covered under Honda’s recent warranty extension for 2013–2017 Odyssey / 2013–2015 Pilot vehicles when the MIL comes on with DTCs P0301–P0304.

NHTSA complaint #11679810 — an unverified report by a vehicle owner.

ENGINE

On March 27th, I was driving my car. My children were with me and we were on the way home from swim practice. With no warning, my engine went crazy. We were sitting at a stop light and the idel became very rough shaking the entire car. The engine was slow to respond to the accelerator and ultimately I decided that it was not safe to drive. I had my van towed to my mechanic who ran diagnostics and confirmed that the spark plugs were misfiring because of oil build up related to a faulty piston ring valve. He explained that it was a common problem with Odysseys. He gave us the options of doing the major repair of the rings that would cost about $5000 or we could replace the failing spark plugs and get 6-8 months out of the car before the same issue would reoccur. Not having a spare $5k on hand we opted for the temporary fix. I recently received a warranty extension from Honda about this exact issue but Honda is refusing to repair my car. They have told me that unless the engine light is on and the appropriate codes are indicated, I can not have the repair covered by the warranty. I took in documents from my mechanic with pictures of the codes, but they will not honor this. They also said that even if they did an inspection that confirmed the piston ring failure, Honda USA would not pay them back for the repairs because the service light and appropriate service codes are not showing. I believe the terms of this warranty extension are in bad faith and put me and my family at risk. Either I spend my own money to repair the car, or I wait until the engine fails and me and my family are stranded on the side of the road. Despite numerous conversations with the service member and customer service, Honda refuses to put in writing their refusal to repair my car under the warranty.

NHTSA complaint #11679169 — an unverified report by a vehicle owner.

ENGINE

My vehicle has a know issue with Honda Corporate with the variable cylinder management that has lead to 7 miss fires in 4 years. The frequent and excessive miss fires are caused by carbon and oil leaking through the piston rings. Honda has attempted to repair the piston rings but that repair was a fail. I’ve experienced a miss fire after the repair and now require another change to my spark plugs recommended by Honda. I filed a reimbursement case with Honda and was notified they will not resolve the issue or reimburse me for the excessive miss fires, spark plug and coils replaced due to their faulty know engine defect. They announced in July 2025 that they were extending the warranty to cover repairs related to engine misfires (DTCs P0301 through P0304) and will last for 10 years from the original purchase date or 150,000 miles. However they have denied my reimbursement after sending proof of miss fire work and payment.

NHTSA complaint #11676053 — an unverified report by a vehicle owner.

ENGINE

The engine has experienced a cylinder 1 misfire condition twice in the last month. In each instance, the spark plug has been fouled with oil and caused the ignition coil pack to malfunction. When the failure occurred, the vehicle was in operation at roadway speeds and placed the vehicle into limp mode with a flashing check engine light and deactivating the forward collision monitor and lane departure warning. In each instance, the vehicle has been towed to an independent mechanic shop where the P0301 codes have been found. I have contacted American Honda Motors and was advised that there are no recalls at this point. Looking online, the 3.5L engine appears to have several issues regarding the VCM system that leads to ring failure and oil leaking into the cylinders. There was a class action suit, Soto et al. v. American Honda, that led to Honda extending engine warranties to 8 years, unlimited mileage, but does not correct the issue with the VCM causing damage. Thankfully for me each time the misfire condition has occurred, I have been close to home so that I have not been left stranded.

NHTSA complaint #11647327 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2015 Honda Odyssey. The contact stated while driving at various speeds, several unknown warning lights flashed on the instrument panel. The contact stated that the vehicle jerked and lunged forward while depressing the accelerator pedal, as the vehicle would shut off. The vehicle was taken to a dealer where it was discovered that oil had leaked onto the alternator. The contact was provided an estimate for the repair. The manufacturer was notified of the failure and the contact was informed that the vehicle was not covered under warranty or recall. The vehicle was not repaired. The failure mileage was 135,000.

NHTSA complaint #11645346 — an unverified report by a vehicle owner.

ENGINE

Cylinders misfire due to leaky cylinder rings. Causes car to ride rough / shake violently. Needs to replace spark plugs, which were completely fouled out with oil. We have needed to have this car towed multiple times and make repeat repairs.

NHTSA complaint #11612640 — an unverified report by a vehicle owner.

ENGINE

The VCM system has failed and caused oil to seep past piston rings and gum/foul up spark plugs. This is a known issue by Honda but they won’t do anything about it.

NHTSA complaint #11589026 — an unverified report by a vehicle owner.

ENGINE

A spool valve leak occurred leaking oil onto the alternator which caused it to fail when driving. When it failed, electrical systems started to shut down. At first, the ABS system indicator lit up. Multiple systems started to fail soon thereafter. Upon pulling over on the freeway, the vehicle was unable to go in reverse. The root cause was a spool valve leak that is well known and consequently puts drivers at risk when driving at high speeds. When driving down the interstate, all the electrical systems started to shut down. The ABS system was the first indicator, along with multiple electrical systems soon thereafter. Once pulled over, the vehicle could not go in reverse as well. I now understand this to be a well known issue as published in Honda Technical Service Bulletin TSB [XXX] However, no information was sent to owners even though Honda has known about the issue since at least March 2020. This puts unnecessary safety risks for those driving with oil leaking onto the alternator resulting in electrical system shutdowns and issues driving. I believe a recall and safety notice should be issued. Yes, the component was inspected by Honda and replaced. The first indicator was the ABS system warning light along with many other systems shutting down. This occurred at a high-rate of speed on the freeway. Upon pulling over, the vehicle also could not go in reverse. I am frustrated Honda has known abut this issue for many years, but has not informed owners nor offered to correct the issue leading to safety issues and costly repairs. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11576721 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2015 Honda Odyssey. The contact stated while driving 55 MPH, the vehicle began to lose power upon the depression of the accelerator pedal. A warning message appeared on the instrument panel that instructed the contact to take the vehicle to a dealer for service. The contact initially took the vehicle to a dealer but due to a high volume of customers, the dealer could not service the vehicle. The next day, the vehicle was taken to a second dealer where a diagnostic test was performed that showed a piston ring failure had caused the engine oil to contaminate the spark plugs which led to an engine misfire. The dealer replaced the spark plugs, piston rings, and cylinder rings in cylinders number 1, 2, and 3. The manufacturer was not notified of the failure. The vehicle was repaired. The failure mileage was 133,597.

NHTSA complaint #11566093 — an unverified report by a vehicle owner.

ENGINE

Honda's variable cylinder management (VCM) system puts inordinate wear on engine cylinders that causes the vehicle to shake and misfire and eventually shut down the engine. It causes spark plug and cylinder coil failures and cylinder damage. This is not due to age, misuse or lack of proper maintenance. The VCM causes engine build up as a normal course of action. This is a known issue that Honda has never communicated to owners of these vehicles. Model years 2011-2013 had the same issue. Honda has offered no recourse, or even communication, to owners of 2014-2017 Odysseys with the exact same VCM (VCM2) mechanism and the same wear and tear on the engine. You can read more about the issues these vehicles have and how common this is here: [XXX] Honda dealerships will replace your cylinder rings (at a HIGH cost) but this does not fix or prevent the issue from recurring. Our vehicle had this work done at 77K miles, but it does not stop the VCM from causing build up and malfunctioning again in the future. Families like ours buy these vans because they are supposed to have reliable engines, and be safe for their families. They sold 450K model year 2014-2017 Honda Odysseys and this effects EVERY one of them on the road today. This is a consumer issue AND a safety issue. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11563505 — an unverified report by a vehicle owner.

ENGINE

At 87,000 miles the piston valves failed in my 2015 Odyssey. Safety was put at risk as the spark plugs would fail due to oil leaking from the piston valves and the engine would flash all the lights and run super hard. Unable to drive it for 1 mile after the spark plugs failed. After the 2nd spark plug failure, a dealership confirmed the issue was the piston valves. 2 Honda dealerships confirmed that this is a known issue with Odysseys, Pilots and Accords and they have multiple vehicles in weekly to address this issue. Honda has had recalls on prior year Odysseys 2008-2013 for the piston valves but does not do anything to recognize this issue remains with the 2014-2017 vehicles. In 2018 the engine/build of the Odysseys changed and the piston valves are not an issue for that year and up.

NHTSA complaint #11559543 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2015 Honda Odyssey. The contact stated that while driving at an undisclosed speed, the RPM gauge was fluctuating. Additionally, the vehicle was shuddering while shifting between gears. The vehicle was taken to an independent mechanic, where it was diagnosed that the PGM-FI software had failed and needed to be updated. The vehicle was not repaired. There was no further information provided. The manufacturer was made aware of the failure, and a case was opened. The failure mileage was approximately 61,030.

NHTSA complaint #11549394 — an unverified report by a vehicle owner.

ENGINE

My 2015 Honda Odyssey has suffered a well known and common engine problem. It currently has 92000 miles on it the engine is being rebuilt by a Honda service department at MY expense. This engine (3.5L) is leaking oil into the combustion chamber in cylinder #3. It has caused a misfire and the inability to maintain speed or control of the vehicle. this has occurred several times and now we are being told that cylinders 1-3 need to be rebuilt, along with some head components that have burned and fouled. When these misfires have ocurred, multiple warning lights (check engine) come on. This is a well known fault with this engine. Honda extended warranties on vehicles with this engine through model year 2013, however they are not covering this issue and it clearly hasn't been resolved.

NHTSA complaint #11547298 — an unverified report by a vehicle owner.

ENGINE

Piston rings allowed oil to enter a combustion cylinder, resulting in misfiring and lack of power. The inability to accelerate was a potential hazard. The vehicle was taken to the dealership and they diagnosed the problem. Internet reports suggest that this is a known problem with this vehicle. The check engine light came on about a month earlier, but the light went off and stayed off until the event that led to the trip to the dealership.

NHTSA complaint #11525425 — an unverified report by a vehicle owner.

ENGINE

I own a 2015 Honda Odyssey EX-L purchased new at the Pacific Honda dealership in San Diego, CA. I wrote to American Honda Motor Co. requesting a partial reimbursement for the cost of significant engine repair work required on my Odyssey over the Christmas holiday, even though the car was well-maintained and had only been driven for 88,700 miles. Specifically, on or about December 14, 2022, my wife was driving our Odyssey with our two young children when the car began shaking and became difficult to drive, the check engine light began blinking, and numerous other warning lights flashed on the dashboard. My wife stopped the car and we reviewed the owner’s manual and learned that the blinking check engine light and other warnings could indicate a critical malfunction, and that the car should not be driven and should be taken to a dealership. We immediately contacted our local Honda dealership, Pacific Honda, and had the car towed, at a cost of approximately $100, to this dealership. The dealership (where the engine repair work was done) said my car needed an “engine rebuild” because the piston rings needed to be replaced and charged me $6,000 for the repairs, despite the car’s relatively low mileage. During the engine repair process, which spanned weeks and ruined my family’s Christmas holiday, multiple employees at the dealership repeatedly admitted that this engine problem was a “common” and “known issue,” and my brief research showed that this same engine problem has been the subject of a class action and recall in the past. In addition, online forums indicate that numerous Odysseys from 2014 through 2016 or later continue to have piston ring, fouled spark plug, and related problems potentially tied to the Variable Cylinder Management system.

NHTSA complaint #11503647 — an unverified report by a vehicle owner.

ENGINE

Began to accelerate onto I-70 west (on-ramp) and the engine began shaking and lost compression to accelerate quickly to merge into the right lane. The engine icon light was blinking and I had to remain on the far right side of I-70 because I could not get up to speed (70MPH). It did not break down but had to drive at speeds below the minimum speed limit. I took the vehicle to the dealership where I purchased it and was told oil had breached and caused the spark plug oil fouled. It required a RING/PISTON job, all new spark plugs, timing belts, O-rings, manifold gaskets, water pump, drive belts, and coolant. Honda responded and would not provide financial assistance. Total cost $5072.67

NHTSA complaint #11503486 — an unverified report by a vehicle owner.

ENGINE

Several times in recent years my car will start sputtering and misfire, losing significant power. Last time I was getting onto the freeway and it was quite dangerous as I was unable to accelerate sufficiently. My engine light also went on. The Honda dealership diagnosed the problem as a problem with the pistons, which needed replacing at a cost of some $4,000. The dealership shared that they were aware of this problem and that Honda had a newly designed piston to replace it. This seems to be the same problem covered by a RECALL for Honda Odyssey's 2011-2013 - but it does not cover my 2015 model. I am attaching info on the recall (Soto et al v. Amer. Honda Motor Co, Case No. 3:12-cv-1377-SI)

NHTSA complaint #11487531 — an unverified report by a vehicle owner.