Tmac06

I posted awhile ago about some engine codes, which stated that there was a misfire on 3 and 5. So today I finally got around to replacing all 6 plugs hoping it would take care of the issue. During the "test run" the malfunction indicator came back on, so I ran a code reader. This time it said 1 and 5 are mis firing.

My next guess is to mark the coils and through process of elimination, switch them around until the 2 bad ones are isolated. I don't know the firing sequence, so it'll be a total guess.

Is there anything else I should look for? Or any better ways to attempt to diagnose this before heading to a shop and having it hooked up?


Thanks!

redbull-1

1 2 3

4 5 6

Front of Car

______________________________
Firing order 1-4-2-5-3-6

Tmac06

Thanks for the firing order. I was having such a google fail earlier and couldn't find it. That and the dealership service dept was closed at 4.

redbull-1

Could be the coils or even a dirty/clogged or bad injector. Good luck.

Tmac06

I ran a bottle of STP fuel system cleaner through it about a month ago. I'm heading out of town next week, itd be a perfect time to run another bottle through I guess.

pw.hondatech

actually if its always 3 and 5 it probably just needs a software update which you would know if you took it to the dealership.

Tmac06

It's not always 3. When I changed the plugs I moved the coils around. So now 1 is missing instead of 3. I'm going to move the two missing coils again and see if it follows them. If not, then I'll take a shot with the software update. When I talked to the dealer before they mentioned it's been a somewhat common problem in my area due to some less than stellar fuel coming in. The tech said if it was a software issue it would be more randomized codes instaed of the same ones. Meh.. Guess we'll see.

pw.hondatech

at first we were replaceing the crank sensor but now its just a software update.can you feel the misfire or its just setting a code?

99blackcivicSi

the update is for a p0171

check your valve lash as well.

pw.hondatech

honda bulletin 08-022 is for a software update for p0301,p0305&p0300.it applies to just 05 v-6 accords.

Tmac06

At first I didn't feel it, i just ignored it and thouht it was just shifting. But now that I've replaced the plugs and switched the coils (bad ones with eachother) the "blip" has gone away as well as the malfunction indicator lamp. I've put about 800 miles on the car with a trip to Seattle with no hicups at all.

If the issue comes up again I'll take it to the dealer when i get home and have an update ran. But so far so good.

I did run another fuel system cleaner, have been running 89 grade fuel. Not sure if it makes a differencer or not, but the min grade in my town is 83, Honda recomends 87.

That's all I've got for now. Thanks for all the info!

Canuck99

The service bullitin does update the software for a missfire, The sensor on the crank misinturprits crankshaft fluctuations as a missfire when in face there is no actual missfire, have updated a few Cars out of the VIN range and its fixed it

KWayRacing

yeah update all the way