2.5 idle problem

markk26 · 10-25-2004, 07:00 PM

Ok , here it is...
The idle on my 97 Legacy GT 2.5 DOHC (125 000 KM) stays at about 1800 rpms.
Out of the blue , no idea what it can be.
Yesterday i changed my oil like i did a hundred time , took a little run around the block , everything was peachy.
Today , take my car to go the store , out of the blue , idle wont get down from 1800 rpms.
Nothing happend , no idea.
The only thing is that i changed from synthetic oil 10w30 to normal Valvoline oil 10w30 , used the exact same brand and model of oil filter.
I noticed that my engine "knock" is getting louder , that's why i'm looking into completly changing it.
Anyone has an idea what it could be?

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Caplin 2.5 · 10-25-2004, 07:52 PM

When you get in your car, give it a few good revs before you get goin, it should drop down below to 1000 w/ ac on and maybe lower without ac on. but if it doesn't drop then i don't know.

markk26 · 10-25-2004, 08:29 PM

It's close to freezing point now here in Montreal ! , no need for a/c !..
And this problem is not at a cold start , it is when i have been driving for a long time and the engine is at running temp.

Still no clue.

munkis · 10-25-2004, 08:32 PM

idle air control valve could be sticking open a bit. Unfortunatly its a very expesnsive part to guess at.

Jay

ImprezaVA · 10-25-2004, 08:58 PM

Try cleaning your IAC valve with alcohol or throttle body cleaner. I've used both recently on my mother's car. It fixed the problem for a week, and then the surging came back again. On the 3rd try, I used WD-40, which is a good cleaner and decent, at best, lubricator. Problem fixed.

-Charles-

10-25-2004, 07:00 PM	#1
markk26 Scooby Newbie Member#: 54698 Join Date: Feb 2004 Location: Montreal , Quebec , Canada Vehicle: 1997 Legacy GT red	2.5 idle problem Ok , here it is... The idle on my 97 Legacy GT 2.5 DOHC (125 000 KM) stays at about 1800 rpms. Out of the blue , no idea what it can be. Yesterday i changed my oil like i did a hundred time , took a little run around the block , everything was peachy. Today , take my car to go the store , out of the blue , idle wont get down from 1800 rpms. Nothing happend , no idea. The only thing is that i changed from synthetic oil 10w30 to normal Valvoline oil 10w30 , used the exact same brand and model of oil filter. I noticed that my engine "knock" is getting louder , that's why i'm looking into completly changing it. Anyone has an idea what it could be? * Registered users of the site do not see these ads.

10-25-2004, 08:58 PM	#5
ImprezaVA Scooby Specialist Member#: 32846 Join Date: Feb 2003 Chapter/Region: MAIC Location: Elkton, VA Vehicle: 1998 Impreza L-SOLD Arcadia Green	IAC Valve Try cleaning your IAC valve with alcohol or throttle body cleaner. I've used both recently on my mother's car. It fixed the problem for a week, and then the surging came back again. On the 3rd try, I used WD-40, which is a good cleaner and decent, at best, lubricator. Problem fixed. -Charles-

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10-25-2004, 07:52 PM	#2
Caplin 2.5 Scooby Specialist Member#: 71203 Join Date: Sep 2004 Location: SoCaL Vehicle: 2005 2.5rs Crystal Gray Metallic	When you get in your car, give it a few good revs before you get goin, it should drop down below to 1000 w/ ac on and maybe lower without ac on. but if it doesn't drop then i don't know.

10-25-2004, 08:29 PM	#3
markk26 Scooby Newbie Member#: 54698 Join Date: Feb 2004 Location: Montreal , Quebec , Canada Vehicle: 1997 Legacy GT red	It's close to freezing point now here in Montreal ! , no need for a/c !.. And this problem is not at a cold start , it is when i have been driving for a long time and the engine is at running temp. Still no clue.

10-25-2004, 08:32 PM	#4
munkis Scooby Guru Member#: 1847 Join Date: Jul 2000 Chapter/Region: Tri-State Location: brokenmotorsports.com Vehicle: Team Broken: V6 GF rallyarmor.com	idle air control valve could be sticking open a bit. Unfortunatly its a very expesnsive part to guess at. Jay