Thing on top of the valve cover (picture)
08-13-2009, 02:33 PM
#1
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Thing on top of the valve cover (picture)
So I was thinking that it was strange that my rear main just suddenly started leaking and decided to replace the PCV valve and grommet just in case it was plugged. I can't tell if the leak has stopped yet but I don't see any new drips.
Anyway.... while I was messing with the PCV thing with the engine running I noticed two things.
1) There was a freaky sucking noise that came and went.
2) When the noise was present the idle would drop and get rough.
I tracked it down to this tihing. (in yellow)
Now if I pull this hose off (again in yellow) and plug it with my finger then the idle gets smoother I still have some slight miss but it's less apparent when I plug this hose.
So what is that thing and what does it control?
I tried to search for it but I don't know how to look for pictures.
Anyway.... while I was messing with the PCV thing with the engine running I noticed two things.
1) There was a freaky sucking noise that came and went.
2) When the noise was present the idle would drop and get rough.
I tracked it down to this tihing. (in yellow)
Now if I pull this hose off (again in yellow) and plug it with my finger then the idle gets smoother I still have some slight miss but it's less apparent when I plug this hose.
So what is that thing and what does it control?
I tried to search for it but I don't know how to look for pictures.
08-13-2009, 02:54 PM
#2
Contributing Member
that would be the AC idle up solenoid, and the two hoses run over to the idle up valve
why it's screwing up the idle though, I dunno
I CAN tell you that when the valve is not in use (ie the AC is not turned on and running), it is essentially a controlled vacuum leak, and the plastic black cylinder looking thing on the end has a small filter element in it
why it's screwing up the idle though, I dunno
I CAN tell you that when the valve is not in use (ie the AC is not turned on and running), it is essentially a controlled vacuum leak, and the plastic black cylinder looking thing on the end has a small filter element in it
Last edited by iamsuperbleeder; 08-13-2009 at 02:59 PM.
08-13-2009, 03:12 PM
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The cap / filter on the end of it allows it to equalize pressure internally so that when the valve is turned off, it doesn't get stuck in the 'on' position by vacuum in the tubing.
The "controlled vacuum leak" is the valve on the side of the manifold which sources air from in front of the throttle plate in order to provide a metered source of air (air goes through the AFM so the mixture isn't affected) when the idle speed is raised by that VSV or by the power-steering unit.
If you're getting air being introduced to the engine through the cap on the VSV, there's a good chance that the unit on the manifold is malfunctioning, allowing vacuum up the hose it shouldn't be or the VSV itself is getting stuck 'half-on/half-off'.
The "controlled vacuum leak" is the valve on the side of the manifold which sources air from in front of the throttle plate in order to provide a metered source of air (air goes through the AFM so the mixture isn't affected) when the idle speed is raised by that VSV or by the power-steering unit.
If you're getting air being introduced to the engine through the cap on the VSV, there's a good chance that the unit on the manifold is malfunctioning, allowing vacuum up the hose it shouldn't be or the VSV itself is getting stuck 'half-on/half-off'.
Last edited by abecedarian; 08-13-2009 at 03:15 PM.
08-13-2009, 04:04 PM
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Try switching the hoses around for the ac idle up valve and see if it works. I had mine flipped around and it was making that noise. Switch the hoses and you should be fine
08-13-2009, 05:34 PM
#5
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I don't really understand the vacuum routing on this thing.......... so many hoses.
So if I switch the hoses and it runs better should I do it? I did a hose re-run a few weeks back and actually lost the codes for the O2 sensor and the EGR (no more CEL) but the CEL for the EGR came back with the odd miss at idle.
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08-13-2009, 06:01 PM
#8
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Yeah but then your competition would be gone......
How would David feel if someone shot Goliath? Yup....... that's how you'd feel............................
Lost, Confused, Upset and lost in history as the guy that might have out wheeled my runner.
Oh did I mention I'm going fishing in the morning? *hugs*
How would David feel if someone shot Goliath? Yup....... that's how you'd feel............................
Lost, Confused, Upset and lost in history as the guy that might have out wheeled my runner.
Oh did I mention I'm going fishing in the morning? *hugs*
08-13-2009, 06:04 PM
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08-13-2009, 06:15 PM
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I just looked on mine and you do have it the wrong way.
Also I think when it is plugged in wrong the AC Idle up valve doesn't work.
Easy fix to re-route the hoses
Also I think when it is plugged in wrong the AC Idle up valve doesn't work.
Easy fix to re-route the hoses
08-13-2009, 06:25 PM
#12
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08-13-2009, 06:34 PM
#15
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FYI work is something you do to live, don't live for work...... you'll die old and pissed off with a pile of money for the kids (or in my case for the EX). Dude take your days and run with them, fish, hunt, wheel, live and love life.
God gave you the gift of life. Take that gift and run with it. You should not show up at the gates of Heaven in a clean suit, with no scars and smiling. You should slide into those gates on your ass with a half finished beer in one hand and a fishing rod in the other and exclaim "Damn that was one hell of a ride!!!!!" Live like you have no future.
Junkers88 3:17 states "No one else can step into your shoes and smile as much as you have".
08-13-2009, 06:57 PM
#17
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Oh so a bumper is going to stop you from wheeling?
FYI work is something you do to live, don't live for work...... you'll die old and pissed off with a pile of money for the kids (or in my case for the EX). Dude take your days and run with them, fish, hunt, wheel, live and love life.
God gave you the gift of life. Take that gift and run with it. You should not show up at the gates of Heaven in a clean suit, with no scars and smiling. You should slide into those gates on your ass with a half finished beer in one hand and a fishing rod in the other and exclaim "Damn that was one hell of a ride!!!!!" Live like you have no future.
Junkers88 3:17 states "No one else can step into your shoes and smile as much as you have".
FYI work is something you do to live, don't live for work...... you'll die old and pissed off with a pile of money for the kids (or in my case for the EX). Dude take your days and run with them, fish, hunt, wheel, live and love life.
God gave you the gift of life. Take that gift and run with it. You should not show up at the gates of Heaven in a clean suit, with no scars and smiling. You should slide into those gates on your ass with a half finished beer in one hand and a fishing rod in the other and exclaim "Damn that was one hell of a ride!!!!!" Live like you have no future.
Junkers88 3:17 states "No one else can step into your shoes and smile as much as you have".
Actually, the kids and I('cause the wife has been onboard the USS Ronald Reagan since May and "might" be back November...
) are takin the weekend off because we've been out and about almost every weekend doing something 
. Next weekend I'm probably going wheelin though! Besides, if 380,000 of us decide not to go to work tomorrow then there's no Air Support for the guys on the ground somewhere. 
Go Navy
BTW, thanks for the pay check!!!!
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