POOR IDLE NOT IdleSpeedControl valve- Help

[jasonvibe]

Hello, my 2005 started having low idle a year ago spring @70k. I cleaned the IdleSpeedControl valve and also because idle was a bit rough too. I also changed the intake gasket AND Checked fuel pressure showed 50psi. Ran slightly better till end of October 2011...when it started the same thing. I had to the idle valve actuator all the way clockwise.... Got idle up to 710rpm. But at full-clockwise it should be much higher. I waited till today 80k to change the whole Idle speed air valve. NOW- the new ISC valve I had to adjust the same way- "full clockwise". Which means something else is the issue. I have NO CELs. As I said, checked fuel pressure @70k miles ...was right on 50psi. BUTcould the fuel filter now be clogging up? BLastly, IT DOES NOT HESITATE WHEN YOU PRESS THE ACCELERATOR AND GOES RIGHT UP TO REDLINE WHEN NEEDED.I checked for vacuum leaks. I did a test by capping off the small "six o'clock" emissions hose/ port= no chenge. I cleaned PVC from the outside.I does not appear to be stuck open. It just idles LOW...not rough unless almost fully warm, cold temps<50f and in gear. IT DOES IDLE almost normal when you drive it constantly. But again, this is not like it should be w/above mentioned adjustment. I have really started getting worn out on this.Anyone else had issues similar to me and it was not the ISC air valve? PS- cannot go to stealer.

[jasonvibe]

Well, I JUST did 2 more things. 1) disconnect battery to reset ECU and 2) cleaned MAF snsr which was not dirty. I should have done just the battery. But now it's acting CLOSER to normal witrh the actuator in the center, no more full clockwise. I will need to do a cold start in the morning to be sure. Because typically it should rev to 1800 or so on start up when the temp is below 45F. And stay there for maybe a minute then idle down as it warms up. We came close to a record today...near 65F. I believe. This cold start seems to be the basis for how it responds to all idle/starting conditions. And thinking back, maybe all I had to do was disconnect the battery and not spend $$ on the ISC valve...? I will post updates to this.

[ehoff121]

Please do post updates because I, too, have a 2005 Platinum AWD with 70k and noticed the same issue. I have not done anything besides cleaning the MAF at oil changes (Mobil 1 5w-30) every 5k, but I'm seeing a cold idle on mornings Racking my brain for things that might be affected be temperature.Could the there be any issues with the throttle cable not opening the throttle plate until warm? Faulty thermostat? Old factory battery?

[jasonvibe]

you should NEVER see idle 500rpm...that is BAD for the engine. My bad idle was as the car approached warm up temp...it just idled lower than the spec 650-750...actually close to 600. Which causes a rumble in you (removed). Cleaning the Idle Air control is the 1st step and for many the only one needed. But when cleaning w/brake cleaner, etc.there are bearings that cleaning will wash the lubricants out. And a few drops of syn. 5w-30 oil like you are using will get the valve shaft to rotate smoothly. There is a link somewhere on the best way to clean. Which requires the throttle body be removed. The ISC valve is under it. You can cheat and take the snorkel off the throttle body and spray carb, throttle body cleaner at the SLOT located @6o'clock...this is the ISC. Then follow w/compressed air. This will help get the carbon junk out. It helps but really need to remove all to do it right. Also mark the electronic part of ISC...it's adjustable. Plus a special 5 point #20 torx is helpful. I got the torx for $3.50. A good auto parts store can find you one. We have had exceptionally warm weather here. So I really do not know if the new ISC valve has made the car much better. I will say it's different and no idle below 650 yet. I really need a morning in the 20's to be sure. I will post results as the weather allows

[jasonvibe]

HERE'S the latest...Yes, disconnecting the battery did reset the engine CPU. Something that must be done when any sensor or control is changed. And things were better till, just 2 weeks after the new ISAC valve was put in...the car idled worse than ever especially with the interior fan on. I returned the unit to Advance. And noticed their's electronic part was different than my original, markings, part# etc.. And did not want another from them, especially when they told me there were none available. But, they were very easy to deal with regarding the return. So I purchased another from someone else(not saying whom) that was identical in every way to original. This latest one has worked better. I thought I had a cure....in my case. But, the latest valve assy. has a delay jumping to correct idle when coming to a stop. And has been like this since it was put in. It's getting worse..longer delay. Oh joy...swap it again, warranty..? But I also consider that maybe the MAF sensor could be going bad. As when the car is driven in the rain or fog,.... W/O window DEF engaged, then the idle is perfect. Making me think the denser humid air is "seen" better by the MAF sensor. I cleaned the MAF sensor too. But it still remains best idle in the rain . My car has no modifications all OEM..no cold air intake, etc....Wow, I am running out of ideas...? could a weak MAF be my issue?