In January 2024 engine began misfiring, towed to shop, all spark plugs replaced due to fouling by oil. June 2024 issue began again, towed to shop, spark plug 1 found to be fouled by oil. Shop states this issue is likely caused by piston ring malfunction known to be an issue in earlier year Honda Odysseys. Honda states issue was fixed in 2014 and newer models, yet many complaints found online for 2016 model.

- Maple Falls, WA, USA

The engine failed, at 90,238 Piston misfire it was replaced 1-3, This happened a second time at 143,000 miles- while the car was moving and same thing engine failed a second time- had it towed in due to the engine not working it doesn't accelerate on a highway to merge has been dangerous- Brought to Honda a few times, because the engine was not working right you cannot accelerate properly on a on ramp and will not accelerate how it should, this is the same issue that was known by Honda. Called Honda they will not do anything more - it was "fixed" according to honda, but still not running how it should it feels like a bad transmission wont accelerate property when- so the car is not safe to drive in any distance misfire ALL WORK VAN WAS DONE AT HONDA DEALER ONLY

- Plainfield , IL, USA

We are reporting a safety concern on the Honda Odyssey that Honda Corporation is aware of on the 2016 Honda Odyssey. They have a defect in the Piston Rings on the Engine. This engine design on the 2016 engine is the same where a recall was called on older versions of the Odyssey and other Honda vehicles. They have not included the 2016 as they say that they haven't had many cases of this version having the problem. With a quick search of the web you will find many people who are reporting or talking about piston ring issues, misfire and spark plug problems on the 2016 Odyssey. They are then asking customers to spend between $3 and $5 to fix this problem in the engine. Which is a known engineering defect! I have kept up with my oil changes and had a well maintained vehicle rating on CarFax. We are reporting the problem to you as when this happened it was extremely dangerous to drive the van. We were stopped at a red light just stopped and the engine was idling when all of a sudden the van started shaking. No sign of a problem prior to this happening. Then we looked and no lights were on but as soon as we started to drive the check engine light came on. We drove the van the couple of miles home as it was a Sunday and the engine had no pick up and go. Pulling into traffic or turning was a danger. This is a danger to not only us in the van but others around us who are not aware of a problem. We drove the van to the dealership on Monday morning. They said that it had caused a bad spark plug and they could clean the area and we may get 5000 to 20000 more miles but that recommended that we would some point need to spend the $4600 to fix the piston rings as well. We did the spark plug repair and they returned the van to us. It still seemed sluggish but we quickly realized that it was having major problems. This is a danger to people in the vans as well as others on the road. Honda should be required to cover the cost of piston ring issues on all years.

- Farmington Hills, MI, USA

engine in this vehicle keeps having a misfire in Cylinder 2 (when looking at engine in car, it is the back side, 2nd from the left) caused by eco mode per honda techs. The piston ring needs replaced per tech and car is 2 model years outside the warranty for this issue that is still going on. its a common issue and is still occurring even is newer models according to the 2 local dealerships.

- Owosso, MI, USA

The engine. I have a 2016 Honda Odyssey. All scheduled maintenance has always been done on this vehicle. I have all the documentation. And I mean it has been babied. It has 110,000 miles. Driving one morning last week and the car just seized up. No warning. No previous warning light. Had it towed to the dealership. The Variable Cylinder Management system had allowed a build up of gunk in the engine. Need an engine rebuild.$5600. Honda just had a recall for cars of the same model manufactured before 2014 for the same issue. As for safety having your engine seize up on the highway is dangerous.

- Seattle, WA, USA

Piston ring failure at 73k miles. Repair costs $5000. The check engine light started flashing and whole vehicle started shaking while driving it on the highway. This is a known issue with Honda and the VCM system they installed on these vehicles.

- Kansas City, KS, USA

The spool valve had a complete seal failure leaking oil onto the alternator causing the alternator to fail. As result the entire electrical system failed, shutting off all propulsion of the van. This occurred while the vehicle was in the high speed left lane on [XXX] @ the [XXX] exit. I had to coast the vehicle across two lanes of 75 mph traffic, cars and large tracker trailers. I was passed by several cars and tracker trailer while coasting across the two lanes of traffic as there was no shoulder on the left side of [XXX]. There were no warning lights prior to the event. American Honda Motor Co. issued Service Bulletin [XXX] on [XXX] to Honda Dealers/Service about the potential for the spool valve casket to leak and fail so that Honda could check for this failure and replace the defective spool valve. The service bulletin covers five (5) different Models and for some Models six (6) model years. The part number identified is 15810-R70-A04, Front Rocker Arm Oil Control Valve (Spool Valve). The correction action is to inspect the front rocker arm oil control valve for leaks and, if needed replace it. The possible causes are the gasket on the front rocker arm oil control valve has deteriorated or the gasket groove is out of SPECIFICATION. Service personnel at Jeff Wyler Honda, 949 Burlington Pike Florence KY 41042, admitted to replacing this spool valve on my Honda Odyssey model several times a month. They admitted that the failure of the spool valve seal can leak oil on to the alternator causing the alternator to fail causing a complete loss of the electrical system and propulsion, seen reports of complete engine fires due to the spool valve gasket failure, noted that the the service bulletin was not attached to my vehicle VIN as did Honda of Jackson 1408 U.S. Highway 45 ByPass Jackson TN 38305. Because America Honda Motor Co. failed to attached the service bulletin to my VIN, my vehicle was not inspected properly for this safety defect. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT

- Jackson, TN, USA

Piston ring failure at 90K miles. Mechanic says repair will cost over $10K. Seems to be a known issue with this year/model based on internet searches.

- Torrance, CA, USA

Pistons Ring premature wear. Car only have 100000 miles on odometer but during 100000 mile service. Honda dealer find abnormal wear of piston ring due to which they suspect leak in combustion chamber which can cause further issue. I bought the Odyssey to last longer, did not expect to do major repairs on only 100k miles and unfortunately that's not the case. Now, I need to make a decision. Pay the 4k get it fixed or keep it as is.

- Chandler , AZ, USA

My vehicle problems started on February 6, 2024 while my daughter was driving back to her house. My 2016 Honda Odyssey EXL started shaking violently at 55 - 60 mph. Upon towing my vehicle to have my certified mechanic to check it out, check engine light was on with codes and misfires. He determined that the variable timing valve solenoid was bad. He replaced faulty part as well as both oil pressure switches and it then came up with check engine light, as well as FCW, LDW, & anti-skid warning lights!? It also had a couple different codes. He then replace other variable timing valve solenoid on front of the engine. After taking vehicle to dealership, to get diagnosed, they suggested several repairs totaling over $3800, which none could insure that it would fix problem (2 of their suggestions were already done by my mechanic). Taking dealership suggestions, my mechanic replaced spark plugs and coil boots, adjusted valves which were fairly close, along with new valve cover gaskets. Now my vehicle runs better but has this engine knock when engine switches from ECO mode to regular full cylinders. Asked dealership about checking/reprogramming control module, but they won't do it!" Any suggestions??" Considering purchasing bypass kit even though I will lose gas mileage

- Manistee, MI, USA

While driving the engine started to run rough and the vehicle started to decelerate. The check engine light and the traction control light came on. I let up on the gas pedal, the van continued to run rough. I made it home and the next day took the van to a mechanic, he told me that he observed oil fouling on the #3 spark plug, consistent with worn piston rings. The van is a 2016 Honda Odyssey with 91,000 miles.

- Toronto, OH, USA

I have had the same issue now twice with my vehicle. The first repair was done in 2020 and covered by Honda under warranty. They repaired Cylinder Block-Piston Rings misfiring. It was I believe about a $3,500 repair when covered under warranty. I now have the same thing happening again. I took it in to Honda for diagnostic test and and i have the need for immediate attention to repair-end of October, 2023. I also already had labor service April 11, 2023 and had a code PO303 cylinder#3 misfire, swapped plugs 3 & 5. Spark plugs causing issues. Again the beginning of October I had to take my vehicle in AGAIN for spark plugs and misfiring. Had the spark plugs changed twice this year. And already had a MAJOR repair for the piston rings on this same vehicle. This should not be happening AGAIN. When my car needed the plugs changed in October 2023 my check engine light came on and was flashing and driving rough. I had to towed to shop to get looked at.

- Milwaukee, WI, USA

The contact owns a 2016 Honda Odyssey. The contact stated that the check engine warning light was illuminated. The vehicle was taken to a dealer and the contact was later informed that the piston ring on cylinder #3 was defective. The manufacturer was notified of the failure but offered no assistance. The vehicle had been repaired. The failure mileage was approximately 48,000.

- Arlington Heights, IL, USA

My wife experienced a sudden loss of power and a very rough running engine at interstate speeds. The check engine light as well as the FSW lights indicated problems with the engine. We brought the vehicle into a Honda dealership for diagnosis. The technician observed an oil soaked spark plug in the #3 cylinder which caused the issue. There were no lights associated with the issue until the sudden loss of power. This dramatic loss of power put her at risk as she limped to a safe area. Honda not only recommends replacing the plug but also all the rings on the rear three cylinders to make the vehicle safe. This is the second time this same vehicle has experienced the same failure and it appears to be an issue with the VCM system on this model. First instance was around 60k and now at 120k.

- Salisbury, NC, USA

My car technician found that my car has leaking problems, and is burning engine oil for a long time which means the engine oil leaking from the engine that might cause fire or damage engine and cause serious engine failure and this is a serious safety concern. I heard this is a common problem for Honda cars. Please advise to recall the vehicles with this problem. Thank you very much.

- Gaithersburg, MD, USA

Per Honda dealership technician: oil seeping into cylinders 1-3 when VCM system is on. Spark plugs are fouled up and causing misfires on engine. Scoring on cylinder 2 also likely due to VCM issues requires engine block replacement. The above engine issues are the reason for blinking check engine light, traction control disabled light, and forward collision warning disabled light to all be on. These ultimately are occasionally causing stuttering/shuddering of the engine during acceleration. While trying to accelerate on an freeway on-ramp the engine appeared to hit a rev limiter at ~4,000 RPMs and wouldn't up-shift to the next gear while doing ~45 MPH with other vehicles behind us also trying to accelerate. Had to let off the gas and gently accelerate over a longer distance/time keeping RPMs low and was able to accelerate to 75 MPH speed limit after merging onto freeway. Vehicle is otherwise in good condition and has maintenance attended to regularly.

- Omaha, NE, USA

The contact owns a 2016 Honda Odyssey. The contact stated while driving 45 MPH, the vehicle started shuddering and was running rough. The check engine warning light and the traction control warning light were illuminated. The contact stated that the failure had been recurring while driving. The vehicle was taken to an independent mechanic, where it was diagnosed that there was oil intrusion on the spark plugs, which caused a misfire. The mechanic replaced the spark plugs and added a fuel additive to the vehicle; however, the failure persisted. The dealer was not notified of the failure. The vehicle was not repaired. The manufacturer was notified of the failure and referred the contact to the dealer for diagnostic testing. The failure mileage was approximately 68,000.

- Chesapeake, VA, USA

On September 28, 2023, the check engine light came on while on the freeway. I pulled over at the closest exit and checked the manual and did as instructed and let the engine cool down. Upon it cooling, I started the car back up and the light did not come back on. Being close to where I was going, I proceeded to my destination. The following week I scheduled an appointment with the dealership to have it looked at. This was scheduled for October 18, 2023. On October 15, while stopped at a stop light, the car started to make banging loud noises and when the light turned green and I stepped on the gas, the check engine light came on again and the car sounded so rough I immediately pulled over and called a tow truck and had it towed to the dealership. This was on a busy 45 mph road, causing a hazard to just have my car fail like that. The dealership discovered that three of the six piston rings had failed, causing oil to leak out and corrode the spark plugs prematurely. I had the repairs completed and have contacted Honda Corporate to inform them of the issue and reimburse me, of which they did not. This has been an issue is previous models with recalls, and this continues to be a safety issue that Honda needs to correct.

- Salem, OR, USA

The contact owns a 2016 Honda Odyssey. The contact stated that while driving at various speeds, the vehicle would hesitate upon depression of the accelerator pedal as several warning lights would appear on the instrument panel. The contact had taken the vehicle to an independent mechanic on numerous occasions where the spark plug have been replaced each time. The mechanic informed her that the vehicle's variable cylinders were the cause of the failure which had resulted in the spark plugs wearing out at a rapid pace. The dealer nor the manufacturer had been notified of the failure. The vehicle had yet to be repaired. The failure mileage was approximately 80,000. The VIN was not available.

- Durham, NC, USA

While driving in October 2022, my car suddenly had the check engine light begin flashing. My car immediately began to lose power and would barely accelerate. Multiple other dash lights then started flashing. I called the Honda dealership who told me to drive it there. I barely made it to the dealership (having to drive slowly, not being able to accelerate, and not knowing if the car was suddenly going to die). The Honda dealership diagnosed it as a failure of the piston rings leading to a catastrophic engine failure. These piston rings needed to be replaced, which could only be done with an entire engine rebuild. This cost approximately $5000. I got the car back and then the next day was driving on a major interstate traveling 70mph. All of the sudden the car completely shut down. It was so extremely dangerous. I had to pull over to the side of the road and wait for a tow truck. The town truck took the car back to the Honda dealer, which diagnosed a timing belt failure. The timing belt and water pump had to be replaced, costing an additional $1-2k. Then in August 2023 the alternator has now failed. This caused the car to again suddenly die while driving it.

- Apex, NC, USA