Have you gone through the "base" idle setting?
https://www.hondaaccordforum.com/for...e-speed-38734/

 

Look closely at the tachometer. Honda skips 250 rpm, so the first line is 500 rpm past zero. Is your car idling at 500 or 750 rpm.

Follow my suggestions in post #5 with the scanner. You can get an inexpensive bluetooth OBD2 reader for ~$20 and a program like torque or torque pro for $7 on your phone. You need to see what your engine computer is seeing to help narrow down the problem. Another more expensive obd connector is bluedriver that I've read good reviews. I purchased it, but haven't had the opportunity to use yet.

 

I worked some more this weekend on trying to solve the rough idle, and hopefully..and more importantly, the conking out while driving issue. First Ill share the idle info.
I worked with my multimeter and the new Bluedriver OBDII scan tool I bought to get some readings.


Thanks Jim for the link, I did do the base idle setting steps and the rough idle is doing much better!
I tried to reach the idle screw with the air filter assembly on and found it too difficult, so I removed it.





I had months ago did the throttle body removal and cleaning, along with all the other stuff I outlined in post #1.
Here is what it looks like now.





With that assembly removed I could remove the idle screw, counting the revolutions to remove so I could install the same.



I cleaned the port out with carb cleaner



and the idle screw itself and put it back in its place


I then hooked up the multimeter pos to the blue tach wire



and then grounded it and cranked the car up and saw readings of 510, so I adjusted the idle screw until it reached 550-560..the reading bounced between the two. I looked at the Bluedriver readout and it was displaying approx 581 rpm. The readings were averaging 20 prm difference between the two devices throughout the tests I ran with headlight on/off, ac with fan on high on/off.



I stopped the motor and reconnected the IACV wire connector and then removed the ECU fuse for a minute, then restarted the engine.
I was at 700 on the multimeter and 700-747 on the Bluedriver app with no lights or ac or radio or fan on.
With the lights on low beam I got 730-740 on the multimeter and 760-780 on the Bluedriver app.
With the AC and fan only on high I got 740-750 on Multimeter and 765-780 on Bluedriver app.

The idle feels better, not without vibration but less now.

PAHonda, from your post #5 you had asked about the live data, here is what the Bluedriver app is showing at idle and revved up a bit.
Would anything in the results show why my engine wants to hestiate and try to bog down?
The error code scan doesnt come up with any error codes by the way.

 

A couple thoughts, maybe you've already figured it out...

- The O-ring on the idle-air screw looks flattened. Get a new one so that isn't a vacuum-leak. A bit of stiff grease on that won't hurt.

- You mention setting the base idle with the fan on&off, AC on&off, etc. With the IACV unplugged, the system is not able to compensate for the changing loads, so the intention is for that adjustment (550rpm) to be done while there's NO loads on the engine. So make sure the AC doesn't run, or the fans, or anything else. If you have to use a box fan at the radiator, to prevent the fans from coming on, then do that. Don't split the difference with stuff running vs. off. Adjust so the idle is 550 regardless if it dies or whatever with the loads on.

Then make sure you allow it to re-learn the idle. That step is important. Don't just reset by pulling the fuse. The part where the ECU learns the idle behavior is why you allow the engine to cool, then start without touching the gas pedal; and allow it to warm up without touching the gas pedal.

 

Since it's better, but still vibrating; have you ruled out external things for the vibration? I'm thinking of things like bent pulleys for the external drive belts, or maybe a loose bracket on the AC compressor or on the alternator? (I kinda wish I had asked this at the beginning)

 

Thanks Ill look for an oring, what size?

The setting I did was done with nothing running but the engine, no AC, No Fan, No Radio, Lights etc.
The fans may have kicked in, Ill need to redo it I guess to be certain.
The readings I mentioned with lights on off, and ac on off was done once it had been reset and the IACV reconnected.
I mentioned them as a side note of the increase in load once all had been done.


Ill re do it all just to make sure, thanks Jim.

 

I just went to look up the O-ring on a Honda-parts site, but it's only listed as together with a new needle valve for about $11. I thought you could buy the O-ring by itself. I don't know the size, you'll have to measure the groove & maybe buy a couple near the size & try em.

 

The fuel trims make it look like you have some kind of vacuum leak, because the short and long term is pretty high at idle.

There are a few methods to locate vacuum leaks. Smoke test, or propane while monitoring the fuel trim with your scanner. I would not recommend using carb cleaner, because you risk starting a fire in your engine bay.