Starting.. rpms drop then go back up.

terranaj98 · Post by **terranaj98** » Sun Jun 03, 2007 9:02 am

When i start my car it drops down to 0.5 rpm then up to 1.25 then back to 0.5 then to 1.25 and then idles out at 1
any suggestions what it could be..
something i think is connected to this problem is
when i shift to drive it drops from 1 to 0.5

any help is appreciated

BSOD2600 · Post by **BSOD2600** » Sun Jun 03, 2007 5:39 pm

Sounds like maybe your PCV valve needs to be cleaned.

555BCTurbo · Post by **555BCTurbo** » Sun Jun 03, 2007 6:22 pm

That would be IAC valve...(idle air controller)

terranaj98 · Post by **terranaj98** » Sun Jun 03, 2007 6:57 pm

so is it the PCV valve or the IAC valve?
and what do i do?

555BCTurbo · Post by **555BCTurbo** » Sun Jun 03, 2007 9:12 pm

PCV is the Positive Crankcase Ventilation valve, and does not affect idle really...

the IAC is the Idle Air Controller, and when they become dirty and old they start giving the exact symptoms you are describing.

First off, if you don't have a Haynes manual for the car, get one, and then it will subsequently show you the location of the IAC and the hose that connects to it...

From there, I usually take some carb cleaner, or throttle body cleaner, and spray it down the hose and let it sit for a few mins, and then run the car, and it should clean the valve out and make the car idle smoother.

terranaj98 · Post by **terranaj98** » Sun Jun 03, 2007 9:19 pm

alright well i just changed the PCV valve.. and it runs better..
i assume that it was stock.. and never WAS CHANGED.. argh
i will try the IAC valve clean thing
when i find it lol

terranaj98 · Post by **terranaj98** » Mon Jun 04, 2007 8:28 am

UPDATE:
i just cleaned the throttle body with some intake cleaner and it seems to not start as high as it did.. which could be a good or bad thing
but it seems like its narrowing down on the right idle.. im gonna see if my mechanic can set the idle. and do a better cleaning then i did

do you guys know where the IAC valve is? where to look.

Post by **Legacy777** » Mon Jun 04, 2007 6:19 pm

Some of these pictures are very useful in telling you where things are.

http://main.experiencetherave.com:8080/ ... injectors/

BSOD2600 · Post by **BSOD2600** » Mon Jun 04, 2007 6:44 pm

555BCTurbo wrote:That would be IAC valve...(idle air controller)

Yea, thats what I meant

Someone wasn't quite awake yet...

terranaj98 · Post by **terranaj98** » Mon Jun 04, 2007 7:42 pm

thanks for the pics..

555BCTurbo · Post by **555BCTurbo** » Mon Jun 04, 2007 7:59 pm

BSOD2600 wrote: Someone wasn't quite awake yet...

Excuses, excuses

j/k

terranaj98 · Post by **terranaj98** » Tue Jun 05, 2007 2:34 am

so today.. it doesnt go as high but it.. idles low..0.5-0.6
do u think i hit something?
im going to take it to my mechanic to adjust the idle so its perfect/normal

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Starting.. rpms drop then go back up.

Starting.. rpms drop then go back up.