well, i started driving today, depressed the clutch and the idle was at about 2300rpm (smooth not bouncing) then the next stop, i depress the clutch its idling at 3500rpm.

then my CEL light clicks on, now im worried.

then i head home, the idle was at about 3800 and i stopped the car.

the computer threw a code 43, its "fuel supply system"

i did some searching and found out that this code usually means an o2 sensor.

the engine ran very smooth and still does, its just a very high idle and it does NOT BOUNCE! this is not a idle bounce problem.

any help is appreciated

 

Have you looked at your throttle plate? Could be sticking....

 

that was defiantly the first thing i checked, it is perfectly smooth, and has no problems.

whenever i start it now it shoots to 3,800 rpm an stays there, if i move the throttle from the idle position it just goes higher.

i also played with the idle adjustment screw and it only adjusted the idle from about 3,700-4000 rpm

totally baffled why it would be staying at such a high rpm???

NOTE: i did recently about a month ago do the FITV idle bounce repair, its been fine since, i checked for any leaks or anything around it and couldent verify anything wrong, disconnected, broken

 

So while the idle is high, what happens when you manually close the throttle..does the idle go down at all?

Your IACV is apparently not doing it's job very well or your valves need an adjustment BADLY...maybe check your valve lash. If you had any kind of vacuum leak the IACV should cause the idle to surge instaed of stay up that high.

 

thats just it, the throttle is completely closed, it should be at idle, but its running at 3,800 rpm!

it's as if you climbed in the car and depressed the gas pedal until it hit 3,800rpm, but the throttle is closed, and the engine should be at idle.

if it could be my IACV whats the best way of testing it on my H23.

this whole thing happened within about 5 minutes so i doubt that its my valve adjustment, i also just checked them a short while ago and they were all within spec.

thanks for the help so far


Modified by h23prelude at 10:59 AM 4/13/2008

 

bump,

 

lil help here...please

 

guys,

i first cleaned my IACV ...didnt change a thing

then i got one from a junkyard.....didnt do a thing

then i put my finger over the TOP hole in the throttle body and the engine went completely back down to regular idle.

my question is where does this hole go to?

and could this big of an intake leak cause my computer to throw a code 43, because i reset the battery, ran the car a little longer and never gor another engine code???

 

sound like your iacv could of have gotten stuck causing the code 43 to pop up and it also sounds like you need to check your iacv wiring is ok and see if it has a input also that hole there is to keep the car running so it dosent choke at idle

 

Did you ever get this problem sorted, as I've an almost identical issue on my 98 B18 civic. It's idling at 3k, but only once it's warmed up, and I've checked & cleaned the IACV, joined the coolant lines on the IACV & put a plate inbetween it and the IM but left it plugged in to bypass it. I've checked all vac lines, all fine. I've sprayed around the TB-IM and IM-head gaskets, nothing. Basically I've done everything I can think of. I'm open to suggestions, I'm quickly killing my clutch at lights & in traffic.

Cheers
Dan.


Modified by prionailurus at 10:01 AM 6/1/2008

 

Well I know this was posted about 2 yrs ago but I recently came across same problem. First code 43 - fuel system , then code 12-barametric pressure sensor. I truly beleived my ECU was screwed, then I realized I had missed one important check, My intake manifold gasket, it was really screwed I was missing a piece, so my air pressure was of the hook, not to mention my cooling system was jacked. Soon as I replaced it problem was solved. No more code 43, or 12.

 

The only way the idle goes up is air getting past the butterfly valve. This could be the cold air valve, the idle control valve, the idle adjustment screw, or a vacuum leak.

The idle adjust and cold air valve can be tested by covering the openings with your finger (just inside the intake). You can unplug the ICV and tell if the computer is sending this signal.

If your intake butterfly is closing completely (throttle cable too tight?), then it may A vacuum leak may be a hose, broken gasket, or loose intake of plenum. Really, you have to leak quite a bit of air to get to 3500 rpm. My vote is that the cold air valve came unscrewed inside.