Fixed Idle Issue...Now car is skipping!! :(

[B18cEG]

Hey bro, sorry to say but the only thing that can explain an idle that high is air getting into the intake from somewhere, pm me if u still got the problem and i will tell u a few things to check.

[FastFwd]

I'm not sure I follow what you mean about the "silicone gasket maker", you need to block off some substantial holes (IACV ports), and I'd have thought that even with a few minutes to cure (which would take a fair while longer with a big slug of silicone) the silicone goo would tend to get 'sucked' into either the plenum, the IACV, or both? If you sucked it into the IACV then you could bung it ip pretty comprehensively I suspect...

Do you mean you deliberately bunged up the IACV by filling it with goo?!

Just a thought. Have you checked the rubber gasket between the IACV and plenum? It could have a leak either to atmosphere around the edge, or from port to port (i.e. air could pass between one port and the other without being metered through the IACV).

Personally I won't let silicone gasket goo anywhere near my engine. I'm told that if it gets into the combustion chamber that it's burnt gasses can 'poison' the cat converter and impair it's function or even make it not work at all. From personal experience I know that it can get 'loose' inside the engine, not a good thing, though in a modern engine it would get caught by the oil filter before doing any damage... probably. It might possibly block the oil pump ports if there was enough of it...

When I used to work in a motor museum we had some come loose inside the engine of a Bugatti Type 35B, caused some issues as the oil filter was non existant (we didn't put the silicone in there, it was somebody who worked on the car before us).

My favourite gasket goos are; 'Aviation Gasket No3', or 'Blue Hylomar', both are 'non-hardening' and dissolve if they get into the oil but not if they stay in place at the gasket. Silicone is fine for gearboxes...

Nah nah u got me all wrong, i am using BLUE HYLOMAR, i checked the gaskets that i currently have and they seemed fine, so i just added some gasket goo just to seal the deal. not much just around the edges. I think the next thing i should do is remove the IACV and block the holes with something and test it like you said.

So sorry im coming to the conclusion that if the idol control seams fine and the idle screw is all the way in that something has to be leaking from inside the intake manifold but before the butterly and really theres only the IACV, throttle body (gasket), Butterfly (loose), or any of the vac lines attatched that could be causing the problems.... OR ECU (sensors)

And that when i plus in and out the IACV even now its making the idle rev to another 1000-2000rpm that is must be something there.

Sorry maybe im just thinking to myself but correct me if what im saying is wrong?

[B18cEG]

reece, check the hose coming from the box on your crankcase, make sure that is all ok, i know it may be too loud but see if you can hear a leak when you block the throttle body with your hand. and check the gasket in you throttle body and where the intake manifold bolts to the head aswell, i strongly believe there is air coming in from somewhere.

[FastFwd]

reece, check the hose coming from the box on your crankcase, make sure that is all ok, i know it may be too loud but see if you can hear a leak when you block the throttle body with your hand. and check the gasket in you throttle body and where the intake manifold bolts to the head aswell, i strongly believe there is air coming in from somewhere.

Yeh blocking the throttleboddy might show a leek...but nah its not the bolts, i removed the throttlebody the other night and cleaned everything out and made sure everything was tight. after work tomorrow ill try taking off the IACV and blocking the two wholes at the back and seeing how it idles then.

[JohnL]

So sorry im coming to the conclusion that if the idol control seams fine and the idle screw is all the way in that something has to be leaking from inside the intake manifold but before the butterly and really theres only the IACV, throttle body (gasket), Butterfly (loose), or any of the vac lines attatched that could be causing the problems.... OR ECU (sensors)

And that when i plus in and out the IACV even now its making the idle rev to another 1000-2000rpm that is must be something there.

Sorry maybe im just thinking to myself but correct me if what im saying is wrong?

You mean after the IACV?

Maybe the IACV is working to some degree but not seating, i.e can work a bit but for some reason sticks and can't close off when it's told to? If this is the case it's a bit strange though that the ECU wouldn't detect the high idle and tell the IACV to remain closed (or as closed as it can be considering it may be sticking open), thus causing no change when the IACV is connected?

Perhaps the IACV is 'stuck' wide open when no power is getting to it, but when it gets power it can close, just not all the way? If so a bit odd as I would have expected the IACV to be closed with no power...

[FastFwd]

You mean after the IACV?

Maybe the IACV is working to some degree but not seating, i.e can work a bit but for some reason sticks and can't close off when it's told to? If this is the case it's a bit strange though that the ECU wouldn't detect the high idle and tell the IACV to remain closed (or as closed as it can be considering it may be sticking open), thus causing no change when the IACV is connected?

Perhaps the IACV is 'stuck' wide open when no power is getting to it, but when it gets power it can close, just not all the way? If so a bit odd as I would have expected the IACV to be closed with no power...

I cleaned out the IACV pretty good, but there was a HEX Key on the one side which i didnt have to be able to pull the whole thing apart. Do you need to pull this thing out to give it a good clean? im heading to a Honda dealer today to buy new rubber rings for the IACV, and throttle body gasket and few other bits and rubbers/gaskets connected to the intake manifold to ensure theres no leeks.

I need to ask how does the IACV adjust the idle when its connected to two ports in the manifold and connected to water? does the water just cool the IACV? what is the purpose of the water?

[FastFwd]

Ok JohnL you would know this. Ive done some troubleshooting with some help of searching around google for a few hours last night.

Ok soo today this is what i came up with. This is before i pulled apart the IACV:


Now ive cleaned it up. I got Throttlebody cleaner and left it soak submerged inside for about 45 minutes. Pictures below:





I also Sanded back some of the rust on the back water casing so it would sit nice and flush.

Then when i put it back on still nothing. Reving up to 5000rpm idle. I read up on the net that if you plug these two holes in the picture below it should sit at stock idol which is what the screw is set at.


The top hole didnt make any difference but the bottom one is sucking all the air threw into the intake so where ever that air is coming from is the problem. Which i seem to think its the IACV. Heres a movie below to show you what i meen.


If anyone can tell me which hole goes to the IAVC and which doesnt that would be great. Because if that below hole is the IACV even after cleaning it twice like i have it has to be replaced.

Ohh also one thing i did check is the Voltage coming out of the sensor wire. it was 2.2-2.5 volts on Accessory i didnt get a chance to start it but i just wanted to make sure the thing was showing some voltage to check to make sure the wire wasnt broken.

[B18cEG]

the hole that you were blocking goes to the iacv, the water port part is just for cooling, inside it there should be like a white plastic spring like thing (like an accordion) with a metal rod through the back of it, when you look into the holes you should see it and you just need to see if it moves freely when you push it, be gentle dont rip it. when your car is cold it should open to rev a little higher, when worm it should shut or nearly shut, it seems like your is stuck open.

[JohnL]

I cleaned out the IACV pretty good, but there was a HEX Key on the one side which i didnt have to be able to pull the whole thing apart. Do you need to pull this thing out to give it a good clean? im heading to a Honda dealer today to buy new rubber rings for the IACV, and throttle body gasket and few other bits and rubbers/gaskets connected to the intake manifold to ensure theres no leeks.

I need to ask how does the IACV adjust the idle when its connected to two ports in the manifold and connected to water? does the water just cool the IACV? what is the purpose of the water?

I haven't attempted to dismantle an IACV. I'm sure you could ensure a more thorough clean if you did, but there may or may not be issues when re-assembling it...??

The water lines are irrelevent to your problem. They don't cool the IACV, their only purpose is to warm it, I assume for the same reason there is water heating for the throttle body, i.e. to prevent icing up in freezing conditions.

The IACV works by drawing air from a port that starts just before the butterfly, air then passes through this port (which is inside the plenum casting, but closed to the plenum chamber proper) to the end of the port which exits at one of the ports in the IACV. Air is then metered as required (as 'instructed' by the ECU) through the IACV and out the other IACV port into the plenum chamber and from there into the cylinders.

[FastFwd]

Ok dude i fixed it...the Lower port that i blocked went to the FITV. not the IACV. but i opened it back up and the thred seems to be a little damaged so this afternoon i went and picked up a new internal part from a wreck put it in screwed it up and DONE!! works.....1100RPM HEAVEN....

But now i have a different problem. i dont know if i've put my ECU out of wake but it seems to be spitting lots of fuel...running extremely ritch...to the point when if i put my throttle down more than 20% it will skip until i take my foot off the throttle...its defiantly drivable now but i cant put my foot down unless i take it easy and bring up the revs for a bit. I think its ECU but i dunno could be something random now

[B18cEG]

is it definetly running rich? is the engine running stable or does it sound like maybe one cylinder isnt firing? it doesnt sound like a wrx when its skipping does it?

[FastFwd]

Nah dude on idle its completely fine...its not Sparks or leeds if thats what your thinking.

Its just when im driving...If the car is in nutral i can rev it and it will be like normal but when im driving and turbo is spooling etc it will skip when i put the eccelerator down to much. almost JUMPY somtimes plus is has like NO POWER wat so ever