Honda Odyssey Forum banner

1 - 9 of 9 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter #1
Hi I am a noob here and hope I am posting in the right place. FYI, I have some car knowledge (do my oil changes, brakes and followed youtube videos to swap the sliding door mechanisms in our old Sienna) but I haven't touched the engine much.

I am besides myself with our 2016 Ody. I let my relative convince me to get it from a used car dealer 2 years ago and let's just say it has only been problems (turns out it was previous lease with an accident O_O).

Slight background. Last year P0420 came on and it was running rough (RPMs all over the place, wooshing noise from the engine, high fuel consumption). Took it to the dealer and they replaced the catalytic converter and that was under the standard warranty.

Sunday the CEL came on flashing with a bunch of other lights so of course I stopped driving it. Codes are P0420 and P0301 and after reading about it, it sounds terrible. So I scheduled an appointment with the dealer but I am afraid of the costs involved because we are over 65k miles and wondering if I need to tow the car there so they don't blame things one me driving it this way. This morning I turned the car one and the CEL is on but not flashing and car doesn't shake so I assume no more misfire at the moment. It still kind of sounds a bit messy.

Now I am reading about the VCM issues and I wonder if this is all related, especially if they find fouled spark plugs. But then again, my car is a 2016 and the covered VCM wear issues are for models up to 2013 I think. I am reading on various forums that newer models are also having similar issues but I haven't read whether Honda covered the repairs if outside the Powertrain Warranty. So would the dealership tell me I am out of luck and to pay all the potential repairs?

If they just keep saying it is the catalytic converter, is that under a separate Emission Warranty for 8 years/80k miles (I think)?

So what could be causing this combo of symptoms based on what I shared. How can I prevent this from happening (install the VCM muzzler,...)?

I'm a bit lost with this. One car family with kids so this really sucks!
Thanks!
 

·
Registered
Joined
·
463 Posts
Classic VCM issues... So 65k total on the van? I think Honda still needs to look at this and diagnose for the record but I would not let them talk you into any expensive repairs.

Honda Odyssey P0301: Misfire - Cylinder 1 | Drivetrain Resource

I'll let the pro's chime in but a Muzzler should be in your future, regardless of this episode. If you've already replaced the Cat, was this done by the dealer so it's OEM? Replacement Cat's are cheaper but don't last so that could be rearing it's head here too but less likely. The Muzzle's are very easy to install by the way, 5 to 15 min job depending on which you select. VCM Tuner II, S-VCM or...

OEM Sparkplugs, from the Dealer or RockAuto only (lots of fakes around, maybe someone else has another reliable source!). If only 65k miles you may just be able to swap spark plugs, run some engine cleaner stuff through the next few tanks of gas and reset the codes [SeaFoam, Techron].

Our '16 EXL had 41k on it before I added the Muzzle. And transmission fluid swaps and updates, critical here too and easier to do than an oil change!

Hang in there!
 

·
Registered
2007 Odyssey EX-L
Joined
·
1,307 Posts
If I had to take a guess, I'd say the issues you're experiencing are connected. The VCM causes oil burning, resulting in the fouled spark plugs leading to a misfire. The oil that's being burned goes through the catalytic converter, ruining it.

I would think you would be OK to drive it to the dealer, provided it's only a few miles, but I'll let someone else chime in on that recommendation.

Keep us updated with what the dealer says is wrong with the car. They might recommend piston ring replacement --- that's their standard recommendation with VCM issues. It's not always necessary (actually, usually it's not). I don't know how likely it is that they'll cover the piston ring replacement cost given that you are out of warranty and are not the original owner. It's only 4 years old, though, so they might. Don't give in to an expensive repair.

Unless they're offering to do the piston ring fix for free or very low cost to you, I would change out the spark plugs (very easy on this van and you can do it yourself if you do brakes) and immediately install a VCM disabling device. There's no other way to solve the problem for good besides the VCM disable. Supposedly, Honda strengthened the piston rings on the 2014+ Odysseys and Pilots, but a lot of people are still having problems. Buy the OEM spark plugs from RockAuto --- don't get them from anywhere else (i.e. Ebay or Amazon) as there are a lot of fakes out there.

Many people report that new spark plugs and a VCM disable, followed by a series of short oil changes (I'd recommend 3K with synthetic oil for a couple times to clean stuff up), seems to slow the oil burning significantly.

One thing that's on my mind --- if the van was burning so much oil to ruin two catalytic converters... did you run the van low on oil? If so, there could be other internal engine damage relating to the oil starvation.

I believe the catalytic converter should be covered under that 8yr federal emissions warranty. If the dealer says that the catalytic converter is the problem again, get them to install a new catalytic converter (hopefully at no cost to you) and then change the spark plugs + VCM disabler.

Good luck!
 

·
Registered
Joined
·
1,674 Posts
Who knows which came first the bad O2 sensor or the VCM issues causing the O2 sensor to foul causing the misfire.

This isn't the end of the world.

Replace the O2 sensor, bank 1 which is the rear one, change the plugs and order / install a muzzler.

The VCMuzzlerII is easiest to install and remove, takes seconds. if youre worried about warranty issues.
 

·
Registered
Joined
·
1,674 Posts
also as noted in many other posts around here, driving with misfires will cause more damage, so dont delay in solving this issue and keep driving at minimum until then.

luckily you're under warranty for everything.
 

·
Registered
Joined
·
3 Posts
Discussion Starter #6
Classic VCM issues... So 65k total on the van? I think Honda still needs to look at this and diagnose for the record but I would not let them talk you into any expensive repairs.

Honda Odyssey P0301: Misfire - Cylinder 1 | Drivetrain Resource

I'll let the pro's chime in but a Muzzler should be in your future, regardless of this episode. If you've already replaced the Cat, was this done by the dealer so it's OEM? Replacement Cat's are cheaper but don't last so that could be rearing it's head here too but less likely. The Muzzle's are very easy to install by the way, 5 to 15 min job depending on which you select. VCM Tuner II, S-VCM or...

OEM Sparkplugs, from the Dealer or RockAuto only (lots of fakes around, maybe someone else has another reliable source!). If only 65k miles you may just be able to swap spark plugs, run some engine cleaner stuff through the next few tanks of gas and reset the codes [SeaFoam, Techron].

Our '16 EXL had 41k on it before I added the Muzzle. And transmission fluid swaps and updates, critical here too and easier to do than an oil change!

Hang in there!
Thanks for replying!
Yeah we are a bit over 65k so the standard drivetrain warranty is gone but I wish this would be been diagnosed last time when we were under 50k. I definitely want them to diagnose the car and have it on record. I hate to pay them the fee if they don't cover it through the warranty though but gotta do it nonetheless lol

Yes, the catalytic converter was replaced by the dealership and covered by warranty. I assume they did this under the emissions warranty saying it was bad rather than finding out what could have made it fail...especially since I literally spent an entire day waiting at/around the dealership for them to look at it.

I will make sure to order/install the VCM Muzzler. I looked at spark plugs from RockAuto but not sure what kind to get? Is there a specific brand and type to get? I do see the NGK Iridium ones at $12 are shown as OEM. I guess I could ask the dealership tomorrow what they charge to sell them to me so I have them sooner.

If I had to take a guess, I'd say the issues you're experiencing are connected. The VCM causes oil burning, resulting in the fouled spark plugs leading to a misfire. The oil that's being burned goes through the catalytic converter, ruining it.

I would think you would be OK to drive it to the dealer, provided it's only a few miles, but I'll let someone else chime in on that recommendation.

Keep us updated with what the dealer says is wrong with the car. They might recommend piston ring replacement --- that's their standard recommendation with VCM issues. It's not always necessary (actually, usually it's not). I don't know how likely it is that they'll cover the piston ring replacement cost given that you are out of warranty and are not the original owner. It's only 4 years old, though, so they might. Don't give in to an expensive repair.

Unless they're offering to do the piston ring fix for free or very low cost to you, I would change out the spark plugs (very easy on this van and you can do it yourself if you do brakes) and immediately install a VCM disabling device. There's no other way to solve the problem for good besides the VCM disable. Supposedly, Honda strengthened the piston rings on the 2014+ Odysseys and Pilots, but a lot of people are still having problems. Buy the OEM spark plugs from RockAuto --- don't get them from anywhere else (i.e. Ebay or Amazon) as there are a lot of fakes out there.

Many people report that new spark plugs and a VCM disable, followed by a series of short oil changes (I'd recommend 3K with synthetic oil for a couple times to clean stuff up), seems to slow the oil burning significantly.

One thing that's on my mind --- if the van was burning so much oil to ruin two catalytic converters... did you run the van low on oil? If so, there could be other internal engine damage relating to the oil starvation.

I believe the catalytic converter should be covered under that 8yr federal emissions warranty. If the dealer says that the catalytic converter is the problem again, get them to install a new catalytic converter (hopefully at no cost to you) and then change the spark plugs + VCM disabler.

Good luck!
Thanks! I really appreciate the help
This pattern makes sense now that you all say it lol

We are close to the dealership so the service writer said to drive it over as long as CEL is not flashing but he wants me to leave it there and take an uber home because he can't guaranty it will be seen. I guess he can tell he won't make money on this car when we live in a very affluent area (I'm not flush with cash like everyone else here LOL). I'd rather he sent me home with a rental lol

I have a feeling they definitely won't cover anything to do with the cylinders but potentially something connected to emissions. I will change the spark plugs after they take record of what they look like which I am specifically am going to ask for.

A couple short oil changes should be easy enough (time to look for more rebate deals LOL). Until recently I used to have them done at the shop and topped off at home between. I wasn't knowledgeable enough to think about how much the car was burning oil and I didn't get any comments from the shop about it. I will make note of it going forward.
 

·
Registered
Joined
·
3 Posts
Discussion Starter #7
Who knows which came first the bad O2 sensor or the VCM issues causing the O2 sensor to foul causing the misfire.

This isn't the end of the world.

Replace the O2 sensor, bank 1 which is the rear one, change the plugs and order / install a muzzler.

The VCMuzzlerII is easiest to install and remove, takes seconds. if youre worried about warranty issues.
ahhh the O2 sensor. That is something else I will ask the dealership about. We don't need to drive since we stock up to go out every 2 weeks... I am just worried about emergencies and can't leave the car at the dealership unless they feel like giving me a rental lol
I have had to reschedule because of work (even being remote is a mess lol) so I am going to the dealership tomorrow and will update you all!

thanks!
 

·
Registered
Joined
·
463 Posts
I "guess" Cat's can just go bad over time, but you could make the argument the didn't diagnose the CAUSE of this problem so this is really on them. They knew at X miles the Cat was messed up, they replaced it; WHY? Did they document any of that? If not, WHY not?

In my lifetime of owning cars I've had to replace exactly zero catalytic converters. It's like they "knew" what was going on, just replaced the part that affected while they had too and let you scoot on down the road knowing you'd be back with other issues.

Whether you do the plugs or they do, they need to be done. I would just pay the "toll" and buy them right there from the dealer if you're going to do them yourself (but check their part number!). Order a Muzzle asap and install, SeaFoam/Techron, oil change (and don't forget your transmission!!!) and see where this all leaves you. At 65k I would be really surprised if you continue to have issues on a '16 but it just depends how much havoc the VCM has caused during your van's lifetime.
 

·
Registered
2007 Odyssey EX-L
Joined
·
1,307 Posts
Catalytic converters can go bad over time... I had a P0420 pop up on my 2001 Camry about 3 years ago at around 140K. It stuck around for awhile, and now it's become a P0136 (oxygen sensor) and the catalytic converter is suddenly fine. Who knows. It's not unheard of for catalytic converters to need replacement as you approach ~150K miles, but certainly not two of them by 65K.

The dealership will likely be more expensive for the plugs but as this is your only car, you're probably better off buying from there rather than waiting for shipping from RockAuto. RockAuto will almost certainly be cheaper, though. The NGK ones that show "actual OE part" are the correct ones.
 
1 - 9 of 9 Posts
Top