Yesterday after doing a timing belt change I had a high idle, I posted about it in a seperate thread thinking I done something wrong on the belt.

 

This is a different thread because I dont think it was timing belt related, after running it a while it went back down to the right idle. Today I took the covers off to find the timing marks to be fine, so I done nothing with the timing.

 

After putting it back together the high idle returned, again I ran it for a few cycles and the idle returned to normal.

 

The only thing I done on both days was to disconnect the neg. battery cable and leave it off for awhile, is there some chance the computer cleared and had to reset to idle correct.

clean out/reseal the idle air control valve. really common on older subaru's for them to get dirty and stick. i haven't personally seen it yet on a newer subaru but quickly found this:

 

http://forums.nasioc.com/forums/showthread.php?t=781242

 

that's a newer Ej engine than yours i think, but the idea will be the same. remove it, clean it out and reinstall. they rarely fail so shouldn't have to replace it.

I took one apart too far one time, and ruined it. The chamber that the coolant lines run in to and out of houses a clock spring , similar to the kind found in a electric choke. Don't take off that housing. There is nothing behind it to clean, and you wont be able to put it back together.

Yes, with the battery unhooked you may get high or low idle. I just went through the same thing. Drive it a little, I usually will fix it's self. Mine gets screwy every time I disconnect the battery, but clears up shortly after driving.

Yes, with the battery unhooked you may get high or low idle. I just went through the same thing. Drive it a little, I usually will fix it's self. Mine gets screwy every time I disconnect the battery, but clears up shortly after driving.

 

I have had my battery diconnected many times, this is the first time I have ever noticed it. Any ideals why this happens?

clean out/reseal the idle air control valve. really common on older subaru's for them to get dirty and stick. i haven't personally seen it yet on a newer subaru but quickly found this:

 

http://forums.nasioc.com/forums/showthread.php?t=781242

 

that's a newer Ej engine than yours i think, but the idea will be the same. remove it, clean it out and reinstall. they rarely fail so shouldn't have to replace it.

 

I am like Mark in next post, afraid to take that thing apart, I will try some carb. cleaner in the hose of I.A.C. if the problem comes back, right now it has gone back to normal idle.

The computer loses its programming after battery disconnect, it takes time for it to relearn it's idle. Yu just need to drive it. Has it cleared up?

clean out/reseal the idle air control valve. really common on older subaru's for them to get dirty and stick. i haven't personally seen it yet on a newer subaru but quickly found this:

 

http://forums.nasioc.com/forums/showthread.php?t=781242

 

that's a newer Ej engine than yours i think, but the idea will be the same. remove it, clean it out and reinstall. they rarely fail so shouldn't have to replace it.

 

I used to just pour gas-line antifreeze into the pickup tube for the idle air control valve and wash away the gunk. VW VR6

It would burn it through system.

 

After a couple of coughs and puffs good to go for another season.

Run some gas-line anti freeze through it to the point of choking it for a start!

I took one apart too far one time, and ruined it. The chamber that the coolant lines run in to and out of houses a clock spring , similar to the kind found in a electric choke. Don't take off that housing. There is nothing behind it to clean, and you wont be able to put it back together.

 

What year IAC did you take apart? I took mine apart on a 95 it's nothing but a coil magnet which controls the shutter. I used a whole can on the IAC and it was fine.. you are right nothing much to clean but I was able to control moving it without fighting a magnet.