Misfire

[Matt1264]

So my accord has been misfiring pretty consistently when the engine is warm. I had the problem before with coils so I had replaced all 6 coils because I didn't want to deal with them going out again and having to figure out which one it was. Now my car will always start fine if its cold but it seems to misfire if i drive it leave it for a short time and then try to start it again. The misfire will go away if i start driving it though. But the whole thing is very consistent. I did have a check engine light a couple times and the code ended up being the typical misfire plus the random multiple misfire. Any ideas of what this could be?

 

[xci.ed6]

a few idea's...


gone when it's cold, only when it's hot, when you shut it off, does it go away or return?

probly returns, if it will start.

start with EGR, clean it and make sure it has no bore scratches

 

[Matt1264]

It only seems to happen when the car is still hot. It wont idle while its misfiring so i have to hold the throttle open a little bit and it will go away on its own after a while. Egr valve was already replaced before when i was having a misfire problem and was trying to narrow it down so ita not that

 

[xci.ed6]

k, well it sounds like too much air/too little gas

EGR check was to look for a possible vacuum leak

next up, check for fuel

This lets me check pressure. I noticed that when hot it is boiling, this also lets me drain a bit (key on/engine off, I use a pop bottle to catch ). Then I get cold fuel (from the tank), and it starts right up.

My next hack (fix?) will be coming.

 

[Matt1264]

where would i check the fuel pressure. also would this cause a misfire or would it just cause the car to not start?

 

[xci.ed6]

yup. it'll cause that. However even that is a vague term.

I used an adapter. It replaces the feed lines connector and has a schrader valve, it was ~$10. It could be re-used on a different car, for technicians, but I replaced the factory 'dampener' with it.