Idle problems can be caused by air in the coolant system. On older accords, there was a bleed valve on the thermostat housing. I am not sure if your accord has one.

All you had to do was remove the radiator cap (make sure engine is cold). Then open bleed valve, then start filling the radiator. Any air trapped in the system would spit out. You would close the bleed valve when a steady stream of coolant would come out of that valve. Then you would top off the radiator.

If the coolant needs changed, this might be a good opportunity to kill two birds with one stone.

Reset the PCM by disconnecting the battery before trying to restart.

 

So i replaced the IACV today.

Upon first start - it idles pretty high and finally settled without surging.

I shut the car off and restarted it - it then started surging again... ARGH. i dont believe there is air in the lines - as both times i torn the IACV off - a decent amount of fluid came out. There is no bleeder valve that i can see on the Thermostat housing either.

So when the surging started again, the Check engine light came on. I took the opportunity to run over to autozone again to see what new found codes came on.

They came out to check the codes and the check engine light is now off.... and no codes.. ARGH - and it started surging while he had it plugged in to.

it appears the surging has stopped, but the idle is still pretty high (1000) and bumps up to 1200 or so when i put it in drive.

Maybe it just needs to be driven more? Does anyone have the "proper" technique for an idle relearn?

John

 

Dbolan,
Your 2007 4-cyl should have a motorized throttle, so there is no cable for you to tighten. Your car is different-enough that you should probably start a new thread. Even on a Honda with a cable, you should NOT use the throttle cable to adjust the idle RPM.

Reilinjw,
Try the procedure that I posted. Look in the DIY section for shop manuals, but even if 550rpm is incorrect as a base idle setting, you won't cause any problem that you can't fix by doing it again with the right setting.

 

Jim,

Just ran out and tried the procedure.

With the car warmed up, when i disconnect the IACV, the car immediatly jumps up to 1500 rpm and stays there ... kinda bounces around a little like it is a limiter, but stays there.

When playing with the screw outlined at #1 on the diagram, nothing happens. when i take it all the way out, there is vaccum, but when i screw it back in, nothing happens. It is bottomed out and no change. There is also no cap which appears in the diagram.

Side note - when i took the throttle body off, no one had a replacement gasket so i made one out of the rubberish material they sell. I sprayed some tb cleaner around the intake while the car was running and there was no change in RPM - so i dont believe there is any sort of vaccum leak.

Thoughts? Kinda lost here.

 

Vacuum leaks? ANYWHERE?

I'm not sure that's a cap in the picture with the idle screw. I think maybe that's an O-ring that goes in a groove in the screw?

Your gasket should be OK, as long as you made all the required small openings that were present in the old gasket. That picture may be sort of a cartoon (for use as a parts catalog) that misses little details like that.

There's a mechanical stop-screw somewhere near the cable-drum. (Normally safe to assume that has never been moved.) That screw is supposed to just prevent the throttle from wedging stuck closed. In other words, the throttle is supposed to close COMPLETELY but shouldn't stick closed. Maybe some former mechanic used that to adjust idle RPM?

I just wish someone with a proper V-6 shop manual would chime in to confirm that the whole idle-control philosophy that I'm aware of, is carried over into the V-6.

 

I've been looking for a vacuum leak, but havent found anything.

I did look in the DIY section for a manual - but do not see anything for an 01 accord.

 

It should be the same for 98-02 but look for V-6 information.

 

Hello,
I have the exact same problem as the other poster. I have a 1997 Acura 2.2CL. I cleaned the throttle body and IACV, gave it a nice rinse with TB cleaner and fitted it back with new gasket and o-ring from Honda and bang..idle surge. I bled the cooling system more than once to make sure I am letting out all the air. Still no change.

I removed the air intake (plastic) and verified that no air is passing through FITV. But I saw air was passing through the IACV even when it was disconnected. I was planning on replacing the IACV but now I doubt is the problem. I tried spraying TB cleaner all around the TB and intake and no change in rpm. So I guess no vacuum. Also, I don't have any CEL thrown.

My car was running fine without any problem before this cleanup. Could I have damaged other sensors when I clened the TB? MAP, TPS..?
I have done this 4 years ago without any trouble!

Moh-

 

I took the IACV bolts off and closed IACV hole on the intake after the engine has warmed up. I did not see any difference in plunger location from cold and warm condition. Does it point to bad IACV?.

When the IACV and FITV valve ports are closed on the TB (with IACV connected) were closed, I saw the engine rpm go down to around 850 rpm and slowly started to creep up over 900 rpm. I also noticed that Throttle position sensor output to vary between 11.8-12.8% when idle (using Scantools.net software). Does this mean my TPS is also failing?

If I have to replace IACV and TPS, that is some serious cash (200+600)!

Any thought and inputs welcome.

 

I checked the resistance between the Yel/Blk and Blk/Blu wires (2P connector to IACV) using a multimeter and a resistance of 0.15M ohm was measured. Is it correct or does it indicate a short?