Idling at 1K
- Thread starter johnathan1
- Start date
okay, i went out and messed with it some more...
With the setup in the pictures, my idle was normal...I also could noticeably hear the BPV sucking in air...right when I hooked the BPV back up, the idle shot straight to 1K...
It isn't my throttle plate, I tried to push it farther closed, but it didn't move, idle didn't change, and my linkage is slack...
I kept blocking things off, but couldn't get the thing to die! I pinched the PCV hose right where it connects to the TB, and the idle went down a bit, but then came right back up...
I also have noticed that I can usually hear an air hissing sound coming from the AFM area, almost sounds like the AFM itself, I looked around, but couldn't find anything strange...ugh, I'm confused as hell.
With the setup in the pictures, my idle was normal...I also could noticeably hear the BPV sucking in air...right when I hooked the BPV back up, the idle shot straight to 1K...
It isn't my throttle plate, I tried to push it farther closed, but it didn't move, idle didn't change, and my linkage is slack...
I kept blocking things off, but couldn't get the thing to die! I pinched the PCV hose right where it connects to the TB, and the idle went down a bit, but then came right back up...
I also have noticed that I can usually hear an air hissing sound coming from the AFM area, almost sounds like the AFM itself, I looked around, but couldn't find anything strange...ugh, I'm confused as hell.
Edit my post...
Nevermind: My BPV sucks under vacuum. I thought they were one way valves, but they are not...
Nothing to see here...
Nevermind: My BPV sucks under vacuum. I thought they were one way valves, but they are not...
Nothing to see here...
Thanks Joel! 
Well, at least it's not my BPV...but I'm getting a new one in a couple days so that doesn't matter anyway.
I can't wait for JJ to get in here and get me in the know!
Well, at least it's not my BPV...but I'm getting a new one in a couple days so that doesn't matter anyway.I can't wait for JJ to get in here and get me in the know!
I did block off the ISCV and the BPV, and the idle would just go down slightly, then up, and the idle does move slightly when the headlights are turned on, defogger, and AC, so that seems normal...
i am kinda suspecting the PS idle up hose... it's kinda old, and that hissing noise seems to be coming from that area..., could i check it just by blovking off the port, or would I have to block the nipple on the idle up valve too?
alright, cool, now I know exactly what to do! I'll take another whack at it tomorrow...I'm gonna figure this out!...dammit!
Yea, so I haven't checked the PS hose, because it is a bit of a pain to get at, as you have to take everything off to get to it, but I will do that tomorrow, so I have to block off the valve nipple too?
Also, as far as the coolant temp. sensor...if that were bad, wouldn't I get a code? The Temp. sensor is also not original...my car had the older square-connector version, it broke, and the only replacment I could find was the one with the newer, rounded-style connector (Aaron said that the sensor was from an 88', and should match the one on my car, but it didn't, so I'm thinking maybe it is from an 89+?) don't know if that would cause my problems...maybe the newer sensor is calibrated differently?
*sigh*...one thing at a time...and thanks for all of the help!
Yea, so I haven't checked the PS hose, because it is a bit of a pain to get at, as you have to take everything off to get to it, but I will do that tomorrow, so I have to block off the valve nipple too?
Also, as far as the coolant temp. sensor...if that were bad, wouldn't I get a code? The Temp. sensor is also not original...my car had the older square-connector version, it broke, and the only replacment I could find was the one with the newer, rounded-style connector (Aaron said that the sensor was from an 88', and should match the one on my car, but it didn't, so I'm thinking maybe it is from an 89+?) don't know if that would cause my problems...maybe the newer sensor is calibrated differently?
*sigh*...one thing at a time...and thanks for all of the help!
can someone explain molecular beam epitaxy to me? :biglaugh:
Yes, the cold idle is in spec @1200 RPMs, in fact, it will go down to normal idle just before the car is at operating temp, then as the temp. rises to normal, so does the idle speed, until it gets to 1000, and then just stays there...
As for the idle up hose...come to think of it, Jose from Driftmotion mentioned to me that there was a crack in an idle up hose-elbow when him an Aaron inspected it for me... wow, I just remembered that! I will replace that vacuum hose, and block everything and see what i find!
And what about the hissing noise, is that normal? Does the AFM make an airy sound when air is passing through it?
Yes, the cold idle is in spec @1200 RPMs, in fact, it will go down to normal idle just before the car is at operating temp, then as the temp. rises to normal, so does the idle speed, until it gets to 1000, and then just stays there...
As for the idle up hose...come to think of it, Jose from Driftmotion mentioned to me that there was a crack in an idle up hose-elbow when him an Aaron inspected it for me... wow, I just remembered that! I will replace that vacuum hose, and block everything and see what i find!
And what about the hissing noise, is that normal? Does the AFM make an airy sound when air is passing through it?
"Molecular beam epitaxy (MBE), is one of a number of methods of thin-film deposition. In solid-source MBE, ultra-pure elements such as gallium and arsenic are heated in separate quasi-knudsen effusion cells until they each slowly begin to evaporate. The evaporated elements then condense on the wafer, where they react with each other, forming, in this case, single-crystal gallium arsenide. The process takes place in high vacuum or ultra high vacuum. The term "beam" simply means that evaporated atoms do not interact with each other or any other vacuum chamber gases until they reach the wafer, due to the large mean free path lengths of the beams."
I get lost after the first comma. :biglaugh:
I get lost after the first comma. :biglaugh:
Where is the idle screw? I don't think i have ever touched that part...
<<Woohooo!! I have 800 posts! I am now a senior member! :naughty:
<<Woohooo!! I have 800 posts! I am now a senior member! :naughty:
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It's only on early cars. 87 and 88 (I think). On the throttle body under a rubber cap.
bigaaron: Matter comes in three forms right? Solid, liquid, and gas. "Source" refers to the form of material used to generate the evaporated atoms. Solid sources are simply small chunks of an element. Think of a chunk of lead. If we heated it enough to give off atoms it'd be starting out as a solid source. Gases can also be used. They're called (duh) gaseous sources. All this take place under a very high level of vaccum for purity reasons.
Thin films are nothing more than deposting a film of atoms of a certain material a certain thickness onto (or into) a substrate, in this case a semiconductor wafer. There are many ways and processes to "grow" films on things. It's how tint gets on window plastics. Optical coatings on camera lenses and sunglasses are other examples of thin film technology.
bigaaron: Matter comes in three forms right? Solid, liquid, and gas. "Source" refers to the form of material used to generate the evaporated atoms. Solid sources are simply small chunks of an element. Think of a chunk of lead. If we heated it enough to give off atoms it'd be starting out as a solid source. Gases can also be used. They're called (duh) gaseous sources. All this take place under a very high level of vaccum for purity reasons.
Thin films are nothing more than deposting a film of atoms of a certain material a certain thickness onto (or into) a substrate, in this case a semiconductor wafer. There are many ways and processes to "grow" films on things. It's how tint gets on window plastics. Optical coatings on camera lenses and sunglasses are other examples of thin film technology.
OK.
If the BPV is sucking air through it,,,
The throttle plate isn't SEALING. It doesn't mean it's cracked open, it just means it's dirty, chipped, etc.
When you unplugged the valve, the air being sucked through it was no longer metered, so the TCCS removed the fuel needed to maintain the high idle, and the revs dropped to "spec".
Fixing the cracked idle up hose will help, but the throttle body is sucking the majority of the air. Capping the ISC inlet should kill the motor, and the adjustment screw is just there for getting things within range if the ISCV.
Pull your 3000 pipe and clean that throttle plate!
If the BPV is sucking air through it,,,
The throttle plate isn't SEALING. It doesn't mean it's cracked open, it just means it's dirty, chipped, etc.
When you unplugged the valve, the air being sucked through it was no longer metered, so the TCCS removed the fuel needed to maintain the high idle, and the revs dropped to "spec".
Fixing the cracked idle up hose will help, but the throttle body is sucking the majority of the air. Capping the ISC inlet should kill the motor, and the adjustment screw is just there for getting things within range if the ISCV.
Pull your 3000 pipe and clean that throttle plate!
Sounds like our Monday morning management status meeting. Implanter down, ASML stepper broken, RIE not holding vacuum after bolt dropped into turbo pump, E-beam offline, backside aligner FUBAR, evaporator contaminated with mystery material, etc etc! Help... Call JJ!! I'll take a 7M BHG anyday compared to keeping a fab line running! :biglaugh:
GaAs: nothing like a little arsenic in the morning!
GaAs: nothing like a little arsenic in the morning!
jetjock said:I designed/worked on pretty much everything but photolith. Mostly plasma stuff. Etchers, sputtering, vapor deposition, LPCVD, ect. I also spent time in the design and fabrication of ion implantation and molecular beam epitaxy equipment. Based on all that it should be obvious I'm also pretty knowledgable about high vacuum gear.
Implanters were the greatest challenge from a control standpoint, not only because of the process and robotics involved but also because of safety. As you're probably aware an ion implanter can be a lethal machine. Not that a sputterer or a plasma etcher can't, just that an implanter can kill in multiple ways. Funny how such a "clean" business is full of so much nasty stuff eh?
I enjoyed my stint in the industry. It was different from my prior industrial experience in that I went from dealing with entire plants to stand alone machines, all of which do what they do on an atomic level. Forced me to brush up on my physics so it wasn't a total loss
Jake, I don't follow. As I recall the CBV control port is connected directly to the intake manifold so the CBV should be open at idle. What does the TB have to do with it?
3p: I hear ya. Fabs are no fun at times. I sure don't miss wearing that damn suit either
3p: I hear ya. Fabs are no fun at times. I sure don't miss wearing that damn suit either
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Ok, I don't think it's my TB, as I cleaned it VERY THOROUGHLY when I was fixing my head gasket. and it wasn't even really that dirty to begin with... not to mention it sealed perfectly, it would even hold liquid! and again...where is the idle screw? (pardon me...I'm having a heatstroke)
edit: I noted today, while sitting in my carport ...that while turning my wheels at idle, the idle would go down when I turned the steering wheel, it wouldn't go up, just down a couple hundred RPM's... what does this mean?
edit: I noted today, while sitting in my carport ...that while turning my wheels at idle, the idle would go down when I turned the steering wheel, it wouldn't go up, just down a couple hundred RPM's... what does this mean?
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