Vaccum

Does anyone know the vaccum on a stock 1993 5.0/Cobra?
I'm getting a consistent 15, which I assume is good, but there's definitely a leak as the car "exhales" when I turn it off. I can't find the leak for the life of me, but it has to be an accessory.
How do I reconcile 15 with the exhale?
Thanks guys.
Brad
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Is the car running bad? If it isn't then the leak is small or there mihjt not be a leak at all. In the old days one could find a leak by spraying starter fluid at various points and when the leak was sprayed the engine would surge. Maybe the power assist unit for the brakes has an issue. Have someone else start the car and then you stay outside and listen for the location of the exhale when it is turned off.
Brad and Karen wrote:

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First of all, adjust your newsreader to 76 lines, and don't try to use HTML on Usenet.
Second, it's vacuum. Weird spelled word. I work in a vacuum repair shop, so I'm tuned into it.
All I've read is that it should be at least 20 at idle. Who knows what computer issues have been introduced?
I don't think that a vacuum reading is worth much with a computerized system in place, because we don't know what it's doing, when it's doing, and why. It's better to read the codes.
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I get 20 to 30 range. 15 not good enough IMHO.
Check the gas fume canester rubber elbow, passenger side up front next to radiator, on the frame rail. Shaped like an L has two different sizes in and out, carbonized rubber part It gets bigger with time and cracks and can fall off, I had to replace with rubber hose. There is no replacement for it, that I have found. Let us know what you find out
Does anyone know the vaccum on a stock 1993 5.0/Cobra?
I'm getting a consistent 15, which I assume is good, but there's definitely a leak as the car "exhales" when I turn it off. I can't find the leak for the life of me, but it has to be an accessory.
How do I reconcile 15 with the exhale?
Thanks guys.
Brad
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Engine vacuum is a relative thing.... IIRC, you are in Calgary which is about 3500 feet. This makes 15 in/Hg at idle pretty good.... (you are also going to be interested in anything that the gauge is doing - pulsing, nosing over, anything...). Those closer to sea level will see idle vacuum closer to 18~20 inches. 30 inches Hg is considered "perfect" vacuum.... ain't gonna happen in the intake manifold...
Even though this car is computer controlled , the basics still apply.... "suck - squeeze - bang - blow"... vacuum gauges, compression testers and the whole nine yards are still very important tools... If a sensor reading isn't outside the "window", there probably wont be a code but there could still be a problem....
Even though this has been an on going concern and you have described it a few times, I'm still having trouble correlating "exhales".... this is one of those things I wish I could here at least once....
I am assuming that you tried locating the noise with a piece of hose and it didn't help? Let's grasp at a few straws, then.... try letting the car idle.... with it running, remove the oil filler cap. Does it come off normally? With the oil filler cap off, turn the car off - does it still "exhale".
Just to refresh ones memory - the sound is definitely underhood? Other than this noise, no other symptoms exist?
Hmmm... a top posted over HTML reply.... Ooooh, I are bad.
<DIV>Does anyone know the vaccum on a stock 1993 5.0/Cobra?&nbsp; </DIV> <DIV>&nbsp;</DIV> <DIV>I'm getting a consistent 15, which I assume is good, but there's definitely a leak as the car "exhales" when I turn it off. I can't find the leak for the life of me, but it has to be an accessory.</DIV> <DIV>&nbsp;</DIV> <DIV>How do I reconcile 15 with the exhale?</DIV> <DIV>&nbsp;</DIV> <DIV>Thanks guys.</DIV> <DIV>&nbsp;</DIV> <DIV>Brad</DIV> <DIV>&nbsp;</DIV></BLOCKQUOTE></BODY></HTML>
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Which would be far less offensive if you'd fix your line length.
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S'funny... in my reader, the lines wrap quite nicely.... Of all the people on usenet, there is only one complaining of line length.... Everyone else is wrong and you are right?

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snipped-for-privacy@telusplanet.net wrote:

Line wrap this time is fine for me, but the top poast f's up the quoting. Outbarf is good about that.
--


"Over here is a chance for a meal,
a young boobie. That's a bird..." - SurvivorMan
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Hey Mechanic.
I haven't been around for a few days... sorry. Getting married. She's practically wearing a new Mustang on her finger and the freaking band alone would have bought me a supercharger... oh well.
So, I took off the oil cap today. It's a rubber push-in type... lots of suction there, while the engine is running and right after I turned it off. Is that bad? I forgot to turn it off without the cap on...my bad.
The sound is just the weirdest... I've thought about this a lot and it's a constant sound when running, like - and this is close as I can come to it - like when you blow into a bottle... THAT sound! ;) When you turn off the car it's like a high pitched hum for about 1 or 2 seconds that fades quickly and dies. It's so hard to explain.
Does any of that help?
I tried the pipe thing and that didn't work. Tried spraying water and that didn't work. Looked at the lines and everything under the hood and they all looked okay, but some are old and I'll replace them all this weekend.
I really do appreciate your time on this... it's so embarassing to have a bright red Cobra make funny noises... :(
Thanks again.
Brad
<DIV>Does anyone know the vaccum on a stock 1993 5.0/Cobra?&nbsp; </DIV> <DIV>&nbsp;</DIV> <DIV>I'm getting a consistent 15, which I assume is good, but there's definitely a leak as the car "exhales" when I turn it off. I can't find the leak for the life of me, but it has to be an accessory.</DIV> <DIV>&nbsp;</DIV> <DIV>How do I reconcile 15 with the exhale?</DIV> <DIV>&nbsp;</DIV> <DIV>Thanks guys.</DIV> <DIV>&nbsp;</DIV> <DIV>Brad</DIV> <DIV>&nbsp;</DIV></BLOCKQUOTE></BLOCKQUOTE></BODY></HTML>
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Hiya Mechanic. Hey, I took off the oil cap and when I turned off the car, no "exhale". Wow. So, WTH is it? Does this help you?
PS: Replaced the lines from the carbon canister today. They were old but it made now difference, as I just mentioned.
Thanks!
Brad
<DIV>Does anyone know the vaccum on a stock 1993 5.0/Cobra?&nbsp; </DIV> <DIV>&nbsp;</DIV> <DIV>I'm getting a consistent 15, which I assume is good, but there's definitely a leak as the car "exhales" when I turn it off. I can't find the leak for the life of me, but it has to be an accessory.</DIV> <DIV>&nbsp;</DIV> <DIV>How do I reconcile 15 with the exhale?</DIV> <DIV>&nbsp;</DIV> <DIV>Thanks guys.</DIV> <DIV>&nbsp;</DIV> <DIV>Brad</DIV> <DIV>&nbsp;</DIV></BLOCKQUOTE></BLOCKQUOTE></BLOCKQUOTE></BODY></HTML>
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