74C5

New member here. My son's car is showing a CEL and stalling from time to time.....not frequent. He's a couple hours away so, this isn't as simple as it could be. It was mine when new.
I ran codes on it today and it showed misfire on all 6 plus general misfire code of P1399. I checked it at idle and it sounded good. Revving to 4000 rpm showed misfiring. The only work on it was a full brake bleed/flush after we did pads on four corners and a bottle of injection cleaner connected at the engine about 3 weeks ago.
So, it has fuel, spark and compression. Sounds like it doesn't have the right amount of one, or more, of those at higher rpm.

There looks to be a lot of history on this issue. I haven't located a definitive fix that works most of the time. It's easier to work on a 1973 TR6 because you can beat the crap out of it to just make yourself feel better.

Am I missing something in my searches?

Lost Again

This could go a few ways.

Does the "miss" happen all of the time - engine temp cold or at normal op temp?

Are the tune up items up to date....the '00 V6 was COP so really just plugs.

slixxracing

I hope someone who experienced this issue can chime in and say what they did to fix the issue. I'm having the same issue with my accord (same year as OP) and my mechanic has no clue on what it could be. I've also been researching and reading up on this topic for the past 2-3 hours and still no solid conclusion on what could be the cause.

DCFIVER

Honda ECMs of that era(96-2002) are extremely poor at identifying which cylinder is misfiring,so typically it will identify all cylinders. A good trick is to erase the codes and then trouble shoot the first misfire code that comes up and ignore the rest. Even better is to utilize mode $06 data if it is available to you....

slixxracing

Stumped onto this SB just now while researching a solution/fix all weekend. I don't know if your symtoms are the same as this SB but check it out.

http://ww2.justanswer.com/uploads/ac..._heat_soak.pdf

Here's a thread created on another forum from a member with the same issue and he said his was fixed going that route.

http://www.6thgenaccord.com/forums/s...ad.php?t=32974

74C5

Thanks for the replies. Cold and hot the behavior shows up. I bought a cheap reader and it doesn't do any other modes.
I was able to lay hands on this engine again. Did the plugs since I don't recall if they were done back at 100k. No obvious signs on the plugs....but, what do I really expect to see on plugs with EFI. Not much.
I ran a HE spark tester on each cylinder and each showed good. HOWEVER, from time to time, coils not being tested were self shorting up to the top of the insulator or the lower edge of it. We cleaned those up just to reduce the potential of low surface resistance and losing spark that should go into the plug. I can imagine a scenario where the monitored spark could cause a code but that is just an intuitive guess.
Did a quickie PCV change out as well since those are so cheap.
Fired it up and cleared the codes. No new codes. Engine revved up to 4500+ without the (cut-out intermittently) type of behavior I saw a couple weeks ago.
There is still a hesitation just off of idle when parked though. Experience tells me that is almost always fuel. My experience is with damnable Strombergs and Webers though so, if I'm wrong, please let me know!
Going to have him run yet another can of Lucas through the fuel and maybe some good gas and see what happens.
A guy I work with made his own fuel injector cleaning setup so I might copy that in a couple weeks if it continues. Gallon can of B-12 several feet off the ground, power supply, hoses and an optional fuel pump. Pull each injector, plumb it to the setup, give it juice to make it open and see if it won't clean up.

Update: Went back to similar to prior behavior after 20 minutes. Feels like a hard miss on one cylinder. Pulled the new plugs, the center front one was tan, others all white. Cleaned up the throttle body, put it back together and still did the same thing. Interestingly, pulled the plugs again and the tan plug shifted to an adjacent cylinder. Shifted coils between the front bank and no change. Each cylinder was getting fuel when cranking with no plugs though.

74C5

And........further diagnosing of the problem made it undriveable. Towed to dealer. 5 of 6 coils replaced by good ones, from another car, made it run properly. Also did timing belt (overdue) and valve adjust.
Ran great for about a hundred miles and CEL came back on. Here we go again.
It is pretty distressing that modern cars are so difficult to diagnose considering the vast amount of sensor technology out there and the abundance of WTF?