Litewait

I'm checking various issues on idle. Or rough idle. When it gets warmed up after 6 minutes.
I have checked the Idle air control valve. (I took it out and cleaned it (it wasn't that dirty, but I had it tested to see if the mechanism opens and closes. And it does.)
I have also checked the fast idle air control valve.
I drained and refilled the coolant.
I tried seafoam. (In the oil, in the gas tank, and in a vacuum hose)
I checked for vacuum leaks.

Next I wanted to check the honda codes. Previously I unplugged the idle air control valve and started it up to see what happened. And that check light went on. I reconnected and I started it.
So when I checked the honda codes. That code came up (no other codes came up). So I disconnected my battery for 5 minutes to reset the code. So now when I check the codes.
The Check engine light stays on solid. (does that mean there are no codes? Or does that mean it's code 0?)
What does the diagnostic code do to display code 0? And what does the diagnostic code to display no codes?


update: 11-19-2018 7:58 am

I have done some research and it appears that it means there are no codes if it's a steady "No blinking = no codes. "
I tried a little bit of seafoam in a plastic cup, and I unhooked the pcv valve hose and sucked it up. After I rehooked the hose up.
It seemed to be a little bit better, and it didn't rough idle for a while. It seemed to drive for a while with no rough idle, even on drive.
But it started up again. Now I went to a shell gas station. I pour some (Lucas) (Complete Engine treatment) 1 ounce per gallon (exactly 8 fluid ounces -with my tank being low)

And then I filled my tank with regular gas (8 gallons). No noticeable improvements right away. Although I went to a few places. And then revved the car up a bit. Then the rough idle went away for a little bit. And it returned. I have not taken it to the highway yet.

I don't know what I will do next. Maybe I'll buy more seafoam, and try to more in the vacuum hose that connects to the pcv valve hose.
Maybe I will ask some mechanics how much they charge for a "Valve adjustment". I think the valve gasket cover has to be replaced anyways, due to minor oil leaks. I might want to do a oil change as well.
As far as the car turning up no codes. I can't tell with absolute certainty . That means everything such as sensors is doing okay, Such as MAF sensor, or the EGR. I think I will look at the manual. Any suggestions would be appreciated.
And also I recently had a mechanic replace a front exhaust pipe on my car. So I'm not sure if it could be the O2 Sensor either. But since it didn't bring up a code for that. I'm not 100% sure.

jbtuning

Our cars are notorious for this issue. It could be any one of those or a combination of a few things. I would go easy on the seafoam right now. From experience, quality tune up components did the trick for me.

Check this link out for reference. Hope this helps if you haven't already solved your issue.

https://www.ericthecarguy.com/solvin...ues-rough-idle

Litewait

Yeah, I was really happy I didn't buy another can of seafoam.

Alright update on this:

Last week I asked for advice on this from a tech. He said it could be a bad fuel injector.
I looked at the honda accord automotive repair manual. And it outlined a troubleshoot guide for this. First thing I did, was loosen the clips on the injectors. Then I took off two 10 mm nuts for the power harness. When the car was running. I unplugged them one by one. For each one there was an idle change, except one.

So I thought it might be a fuel injector. If you take a screw driver you can hear them click. There was no way for me at the time to check if it was a failure of the power harness. But anyways, I got a fuel injector from a salvage yard. I cleaned it. And I switched that out. No change. Finally, I decided without changing the firing order. I changed a spark plug wire. To the one were the idle wasn't working. To another one. Next I checked the power on that one. Finally there was a change. And you guessed it, where I switched out the spark plug wire to another cylinder. That one is were there was no change.

So I figured out what spark plug wire it was. Since I couldn't buy them individually. I decided to order a couple of different sets. I finally switched the bad one out with the good. And now it's working. No rough idle anywhere to be found.

Only thing is after I changed the injector. For some reason, when I put the key in the car and put it in a on position. And wait for a while. Both the battery and the oil icons stay light up. When I start the car they go away.

Now I had the battery replaced because it was no good. And that was under warranty. I had the starter and the alternator checked at a part store. And they were both good. I had the oil changed as well. They still show up. But not when I'm driving. I don't know what the cause is, or if I should worry. But nothing in my troubleshoot manual states anything much about this. It only states that if it's running, it should be checked. Who knows. But the car is running really good.

Any advice on this? Would be much appreciated...