Does anyone knows the function of the "ISV" valve?
02-28-2005, 10:44 AM
#1
AudiWorld Super User
Thread Starter
Join Date: Feb 2005
Posts: 2,001
Likes: 0
Received 0 Likes
on
0 Posts
Does anyone knows the function of the "ISV" valve?
<center><img src="http://pictureposter.audiworld.com/87791/s4_171.jpg"></center><p>I am cleaning/checking all the valves with a carbon remover spray and I am curious about this valve function and state; With no wires connected it allows 100% air flow.Is it a normal state? Can I spray the carbon remover to it's interior, or is this valve too fragil to do that kind of procedure?
02-28-2005, 11:03 AM
#4
AudiWorld Super User
Join Date: Sep 2000
Posts: 9,705
Likes: 0
Received 0 Likes
on
0 Posts
That is the correct Name ISV=Idle Stablizer Valve
It is fine to spray out w/ carb cleaner and let drain/dry. I seem to recall that mine was "closed" when no wires are connected. It was opened about 1/8-1/4" when I had mine off...as I last recall.
02-28-2005, 11:42 AM
#5
Not normal. When disconnected, there should only be a small gap, not completely open.
It stabilizes the car's idle by micromanaging the air intake. It is called the ISV or Idle Stabilizer Valve. Use only carb cleaner to clean it and allow it to completely dry before before re-installing. You should also lightly lube it. Do not allow fluid to sit in there, only spray through it. I think your is broken as it should have only a small gap and not be completely open when disconnected. I have known cars to idle fine with a bad ISV, but many can't idle at all.
02-28-2005, 12:12 PM
#7
AudiWorld Member
Join Date: Oct 2003
Posts: 278
Likes: 0
Received 0 Likes
on
0 Posts
Try GM Top engine Cleaner. Fantastic results on ISV and throttle body.
I have just completed trouble shooting my idle issue with my car. It was only happening once a day, especially when real cold out. I cleaned it with carb cleaner first and a q-tip, but I could not remove all the deposits. The idle problem came back after a couple days. I talked to my mechanic and he said that carb cleaner is for dry cleaning bench purposes only. He gave me a product called GM top engine cleaner. This product removes carbon and buildup like magic. With one spray it drips away and leaves behind a lubricant to keep the valve working great. I have not had the problem since. I have since read about this product on a corvette page and they state the same abilitys of this product. I'm not a GM fan but this product seems to be fantastic and wanted to pass it on.
Trending Topics
Thread
Thread Starter
Forum
Replies
Last Post
QCRAZY
A6 / S6 (C5 Platform) Discussion
53
05-02-2017 07:49 AM
For those that have bypassed their N249 valve.. what did you use to cap off the line from the valve?
Lightweight-USPowah
Performance and Tuning
1
09-23-2003 12:18 PM
