i tried that on a 98 Civic, couldn't get a hose down the filler tube so I pulled the pump and went at it that way. don't know about ODY though, presumably the same though.

I have cars that have much older gas in them, way past 11 months. but I do use Stabil fuel stabilizer. hard to say, but it's not a bad place to start... CL should use premium fuel too, so when you fill up, remember that.

Misfires on these engines have also been linked with valve lash adjustment or crappy plugs. I use Denso and NGK exclusively in all my cars.

 

It may not be the fuel, because if it is, even at idle, you should see signs of it. And you said its smooth at idle. Why not just let it idle until the fuel goes to 1/4 tank or even empty.

You can remove the bottom hose of the filler neck connected to the tank. But with 3/4 full it might be a little messy. Doable, but you need a big drain pan and 3 - 5 gal fuel containers. If you jack up the rear the tank will tilt a bit away from the hose nipple. When I had a fuel tank leak, first I though I wanted to drain the fuel tank too. But I chose to drive the car until its low enough that when the bottom hose was disconnected, no fuel came out.

 

Here is the thread with pic of the bottom hose. http://www.odyclub.com/forums/24-1999-2004-odyssey/280241-99-fuel-filler-tube-leak.html

 

I really doubt the old gasoline is the problem, but many times the symptoms you describe can be bad timing. Recheck the timing belt to make sure it didn't jump a tooth or two.
Buffalo4

 

I'll check it. I had a local guy that used to be the service manager at the local Honda dealership do the belt, seals, and valve adjustment for me. He left the dealership and started his own shop. I'd be surprised if he did it wrong and I'd be surprised if it jumped at first startup.

 

I decided to check the coils again. I found that unplugging #5 made no difference. I swapped in a good coil and it made no difference. Im halfway through a compression check (I had to leave to go to a cookout). That cylinder was the highest of the 3 I've checked at 185psi. The others were 175 and 180. It looks like I have a wiring issue.

 

That spark plug is clearly wet with gas too.

 

Sounds like you won't have to drain the gas tank, after all,
Nice troubleshooting.
Hopefully you will be able to find the cause of that no-spark cyl and happy to hear it has really good compression.
Don't forget to put in another spark plug, since they can also fail, even newer ones.
Buffalo4

 

It was wiring. I made a mistake when hooking up the intake runner control module to the ECU. I've got it fixed now. No codes at all!! It's running great!!