Every once in a while my car will rev up. Like it feels the car can drive it self. I just did a tune up to it. I seafoamed(helped a lot last time) and then changed the plugs and air filter. Car runs great now, but it sometimes still does this high idle thing. You can feel it. If I pop the car into neutral it will be revving about 2000 rpms or so. It will eventually go back down and then be fine. But sometimes while driving in the city lots of stop and go it will do this more. I think it could be a possible that the IAC is really dirty or needs to be replaced. My question is now what do you all think on here? How can I get to the IAC? I didn't know what it looked like.

 

It's bolted under the TB.

I'd say start there with cleaning the IACV.

 

what plugs did you use- brand?

in my experience dirty IAC tends to make rpm fluctuate around 1500 more than hang the rpm on decel-its IDLE control

Im thinking this one may be a TPS issue- throttle position sensor hanging up
or a smog device for decel control is hanging up

Is the throttle return spring at TB clean and lubed?
The hose clamp for master vac port installed after seafoam?

Driveabilty experts??/ what do you think

 

It wasn't the A/C compressor kicking on right ? Just wondering.

 

rpm 2000 if you slip into nuetral-
doesnt sound compressor idle compensation related to me

 

well i was just wondering, my bad.

 

hey all your input is greatly respected and appreciated- You have made several good catches that I have seen already! you know about cars- share your best guess!!

That line about N and 2000 made me think decel control or damaged-stuck throttle return springs or cable prob or even TB air plate dirty
Seafoam everything!!
(make aerosol with a plastic spray bottle from liquid seafoam-they keep shrinking the deep creep can size but same price)

If its consistent problem,does it every time you lift off -- I would lean towards a smog control valve that slows rpm drop when you lift- to keep excess gas from flooding the system--
(thats why many motorcycles backfire on decel- unburnt gas floods the exhaust, then ignites in the exhaust-works great to get tailgaters off one backside~ hehehehe)

Im just trying to narrow the OPs focus on prob,,I can be wrong--its happened before
The wife will be happy to confirm that for you~

So it could eb egr ports plugged for all we know- that will make funky stuff happen

according to our supermod- every 75kmiles it needs to pull the intake manifold and clean the egr ports inside

 

I already seafoamed the intake manifold. It is not always happening just sometimes. I haven't tried to really clean the TB. I was thinking more IAC because it only happens sometimes. Its not the compressor. The A/C is always on now its 90 plus here. The car runs great. After I did the tune up it feels like it picked up 10 HP. I may take the intake tube off and spray some TB cleaner in the TB. I have some of that as well as some more seafoam. I'm trying to really figure out how to take the IAC off. Is there a good picture tutorial around. I didn't really find one. I am pretty mechincally oriented person.

BTW no codes.

I used standard NGK platinums.

 

i think its the iacv i had the same problem cleaned it and it was ok now its starting to do it again the mechanic said i should replace it cleaning only lasts a while

 

iacv is on the bottem of TB unit
most remove TB from engine and flip over to do
but Ive heard it can be done on the car-ck it out with a mirror--
use new gasket from TB to manifold
clean the air plate inside tb well with carb cleaner or similar

try a can of seafoam in just under a HALF tank of gas

 

stop by a parts store and ask for a code ck- there can be some without warning lights and should be some -since this is a serious problem
car wont pass smog like that~

 

I may just have to break down and remove the TB. Should I replace the part?

 

remove the small round iacv cover and clean the part inside