TexasHonda,

Update:

Took the car to another mechanic and he couldn't scan for any thrown codes because the person before me messed the wiring up so bad underneath the dash.

Got the car to idle with no accessories on at around 850. Same problem with AC though, soon as it comes on the car bogs down by about 500rpm. First question is that is this considered normal? Two different mechanics have stated that this is how it is with these hondas but I cannot see Honda designing a car that bogs down and vibrates badly when under load. (and drops the RPM so much)

Second, I was given a solution in a can that I can spray into the intake and watch the dye leak out to detect vacuum leaks. (can't remember what it is called). Other than that I have a junkyard close by with every make and model import you could want. Would it be worth the effort to grab an IACV off one of the accords there, clean it up and try it in mine? I am trying to eliminate the issues one by one.

Thanks for your time Texas (and anyone else who may post).

 

Second update, when coming off the throttle the car will idle about 1200. You can tap the throttle and then it will come down to about 800, but will usually dip to about 500.

 

When idle decays to 500 rpm the engine is starving for air. When running at 1500 rpm, there is excess air. Something is causing the conditions. Most likely candidate is IACV or throttle plate. Clean the throttle plate on both sides and bore around plate.

good luck

 

Texas,

Picked up an IACV from a junkyard (the donor car had about 90k on it) and cleaned it up and put it in. No change. When the car was fast idling you could turn everything on and it would only drop about 200RPM.

If the car was brand new, what kind of RPM drop would be considered normal when the accessories come on? 100rpm? 200RPM? I have to take it back and get the AC serviced so I want to make sure the mechanic understands what I need.

I have the car idling without accessories at 850 to 900 rpm. When the AC kicks in the RPM drops below middle hash mark. Since the AC needs to be charged the compressor kicks in every two seconds which causes it to bog down and never stabilize.

Thank you for your continued assistance with this issue.

 

Either your IACV is disabled (wiring or connector fault) or the air is not getting to the IACV (blocked inlet or outlet passage). If IACV is working you should be able to feel the solenoid opening/closing rapidly w/ vibration in the IACV.

Disconnecting the IACV should cause the idle to drop to around 750 rpm. If lower, the inlet air bleed screw needs to be opened to set the non-compensated idle speed. Do not adjust throttle plate stop.

Have you cleaned throttle plate and throttle bore around plate.

IACV will easily compensate for AC, Alternator loads as they are added to maintain idle speed,...if system is working correctly.

good luck

 

Yeah I cleaned the inside bore, the outer and inner sides of the plate, and anything I could see inside the TB that had any buildup on it. I'll go out and warm the car up again and then check for vibrations in the IACV.

I was gonna ask where the air flow was going into but I realized my wrong assumption. The coolant does not actually flow into the inlet and outlet screen. I took off the plate where the coolant lines are and only saw a depression. What does the coolant actually do in there?


Thanks!

 

Second update:

without the AC running I disconnected the IACV and was going to adjust the idle when the belts started to squeal very loudly. Shut the car off and reconnected the IACV then restarted. Seemed to idle fine but the AC doesn't work now.

Pressing the AC button in the car, it doesn't even light up now. Wth happened to it? I can see the AC compressor turning freely.

Before this I turned the AC on and felt the IACV. It was hard to determine if the valve was vibrating over the motor itself. should you be able to hear it click?

 

I went out and started my 94EX to see if I could feel the solenoid movement. I thought I could but could not be sure. I also listened w/ a tube and could not hear a recognizable sound. I don't think you can confirm IACV function w/ sound or vibration.

I disconnected IACV to see how it would run. Idle dropped to zero and car stalled immediately. I restarted and was not able to get a stable idle. Even w/ foot on throttle it cycled a bit in rpm. I reconnected IACV and it stabliized. My guess is my IACV, throttle plate, and bore are dirty and barely able to compensate. I will remove and clean soon.

Try disconnecting IACV and see what happens and whether you can get a stable idle. You should be able to get a stable idle w/ everything off at around 750 rpm w/ adjustments of idle air bleed screw as required. Then reconnect IACV and see if things are better.

good luck

 

Third Update,

Left the car sit for about four hours and came back.

Now the AC works normally again but it squeals badly when its on. Before all this I disconnected the IACV (all accessories off) and was able to adjust the idle close to 800. Reconnected the IACV and the idle remained stable. Turned on the AC and it dropped back down to right underneath the middle hash mark.

I am going to use my wife's camera and take a video of whats happening and then post it to youtube so you can see what is happening. It may be a few days for it.

I hope this isn't heresy here but assuming I can't find this issue, would I be better off taking this thing to a honda dealership instead of local mechanics? I understand they would charge an arm and a leg but every time I take the car in to a mech they don't freaking listen to what I need done to the car.

 

If AC/Alternator drive belt is reasonably tight, you may have a compressor that is failing and pulling rpm down due to excess load.

Suggest you try to turn the ac compressor clutch plate (inside of the pulley) by hand w/ engine off. It should rotate easily w/ just slight resistance as pistons compress gas. If stiff or grinding feedback, then something is wrong. Post back for path forward.

good luck