Drew082

Like the title says, every single one is misfiring, according to the ODBII scan. There's no emissions codes showing up so I doubt it's a bad cat. I'm thinking coils or valve adjustment.

Sound like this is feasible?

Drew082

Data logged the van and nothing out of the ordinary showed up. Had the codes cleared and reset the ECU and it seems to be running fine for now. I'll just keep an eye on it and see what it does.

jonshonda

Stop driving it now and check all your coils and spark plugs.

Its a well known common issue on the 3.5 V6 that the spark plugs back out, arc to the head, and blow the f@ck up.

This just happened to me, codes said misfires, and then it blew the spark plug out of the head. 06 Pilot w/ 101k.

Its gonna cost me a ton.

sleepysideways

Sorry to dig up this semi-old thread but I am having the same problem.

I have an 05 Odyssey EX-L with VCM and it gives me misfire codes for all cylinders and random misfires from time to time. It doesnt happen all the time since its not always running rough. But I clear the codes and it comes back on within the next 70 miles of driving.

Does anybody have a definitive solution to this problem?

barcalan

The problem has to do with one the ignition coil not working properly and needing replacement.
I had the same problem a week ago and I resolved it by following the instruction of this YouTube video:


Good luck!!

sleepysideways

Thanks for the reply barcalan.

I wish the problem was as easy as a bad coil pack. I forgot to mention that the spark plugs have been replaced and all coil packs have been tested to ensure proper working order.

Still no good though....

Accordman1

Well, I hope you had figured it out by now. Not sure what is the circumstances that lead to the misfires. I heard from several places that the engine misfires on newer Honda is mostly due to people replacing spark plugs with the wrong ones. They need to be NGK Iridium long life, or Denso, not Autolite, Bosch, etc. The other potential issue is spark plug gaps or ignition coils in your coil packs. If everything checks out, the next step is to check the fuel pump and your intake EGR valve.

GoLowDrew

I'm late to this recent post on this thread. The plugs go bad on the V6 because of the VCM. It's common and an easy fix. Replace the plugs and one should be fine. Honda does have a software update in the TSB, but you will have to pay for it. The software makes the VCM less sensitive and kicks in less. I did the update on my Odyssey. No difference in feel or MPG.

Up to you. You can replace the plugs and be on your way. Honda said the plugs are 100K mile. I would changed them out earlier. Avoid the problem and save you some $$$$. Maybe at the 50K mark (?). My plugs went bad at 54K miles.

Dealer will charge you $120 + parts (plugs)+ labor.

Plugs are $7-9 each at Autozone.

As for the iridium plugs, they are "OEM" replacements and more to do with emission and required in states like CA.

You can use "regular" plugs (the $7-$9 ones). They will work just fine with no sided effects like less MPG.

When you go to Autozone they will of course push the Iridium ones.

molsoncanadian

Also for 05+ Odysseys make sure the #5 plug is real snug as this one tends to back or "blow" out.

GoLowDrew

I was at Oriely's the other day getting some oil and I asked this question. They could not tell me why iridium plugs were needed. According to their database, all of them are OEM replacements. In fact, they try to push the mid-level (cost) ones like Bosh double platinum. So I can spend $12 each (iridium) or $4 each (cheapest).

Accordman1

As I mentioned earlier, the NGK Iridium is the OEM plug for newer Honda cars that will last the 105K service life. None of the cheaper platinum plugs will last more than 50K. I used to have the platinum plugs on my older 93 Maxima and they worked fine for that car. I don't have any issue yet on my Honda with 60K or more even with VCM. I don't know why VCM would be hard for the plugs. I would not replace them until they are at 100K or until they cause engine to misfire. If I am going to take time to get them replaced, I may as well put in the right ones, saving me from having to replace them sooner. I have heard many reports on engine misfires from people replacing spark plugs with the platinums rather than the OEM spec. I would not trust the regular auto part stores to know more about your car than the maker.

curiouspeter

I have a 2005 honda odessay with a 3.5 v6 engine. When I start it the engine the service light comes on and is blinking.if I drive it , it runs rough and soon will die out and be hard to rdstart. If I start it and when it starts blinking I turn it off and restart it it will blink again, but if after starting aND turning it off about 5 times it will stop blinking and just stay on without blinking. It will run fine then and I can drive it without any problems. I took it to a honda dealer and left it with them for 2 weeks and they could not figure it out. We've been starting it and stopping it till the light is solid and driving it like that for about 6 months, after going through that sequined it has been fine. Yesterday after running about 20 min it finally slowed down to 500rpms and wouldn't accelerate any higher in rpms. It would start up but would not accelerate above 500rpms. I need to replace the positive cable for the battery but what else could cause it to suddenly cause the engine to react like this? I thought, catalytic converter or fuel pump but I can't afford a big repair bill. The van has 220,000 miles but we've changed the oil every 3000 miles and there's no rust and every thing b else works fine. We love the van and up till now it has been great. Please give me some advice if you can. The honda dealer was no help at all. Thank you. Waleyemstr@gmail.com

bhfailor

Thanks for posting, panman1. Wondering how hard it is to replace the air pump. A search indicates that the price is in the range $180-280.

This is what happens for us - we have a 2005 Odyssey. We do something that abruptly changes the operation of the car, like turning sharply or stopping abruptly. The engine seems to run roughly and the RPMs seem to be limited. The check engine light and other assorted lights come on (e.g. airbag, AVS, airbag side, and others). We turn off the car and wait a few seconds. When we restart things are fine. Most of the lights are not longer on and the check engine light eventually goes off.