Having a hard time finding a vacuum leak UPDATED *7/18*
#1
That Guy
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Having a hard time finding a vacuum leak UPDATED *7/18*
Having a very hard time finding my vacuum leak(s). I would expect it is a vacuum leak (serious) because cold start I'm at 9-10 in.hg and when warm 13-14 in.hg. I found one intercooler boot had a big tear in that, replaced it... still at same readings. Stupid Porsche Y fitting going up to the fuel rail and bypass valve was ripped... still the same deal once fixed.
I tried spraying brake parts cleaner on fittings and along lines but the idle didn't change at all.
Is there any way to pressurize the system (or vacuumize the system) while at the same times being able to hear or see the leak? I really don't want to take off the intake manifold to realize it was some easy connector.
ALSO: I would love to redo the vacuum system with some form of line manifold where the banjo bolt is not in the intake manifold. So i can just run silicone lines to each piece that needs a vacuum line and get rid of the stupid, gumbled set up Porsche came up with.
Updated!: Well i ghetto engineered my own presurizing system and it worked like a charm. Only sad part... Vacuum leak is coming from some thing under the intake manifold . I got soapy water and sprayed it on all the connections there and down at the intake manifold connects to the head and got nothing. I got down real close and you can hear it coming from under the intake manifold.
Any ideas what it might be?
I tried spraying brake parts cleaner on fittings and along lines but the idle didn't change at all.
Is there any way to pressurize the system (or vacuumize the system) while at the same times being able to hear or see the leak? I really don't want to take off the intake manifold to realize it was some easy connector.
ALSO: I would love to redo the vacuum system with some form of line manifold where the banjo bolt is not in the intake manifold. So i can just run silicone lines to each piece that needs a vacuum line and get rid of the stupid, gumbled set up Porsche came up with.
Updated!: Well i ghetto engineered my own presurizing system and it worked like a charm. Only sad part... Vacuum leak is coming from some thing under the intake manifold . I got soapy water and sprayed it on all the connections there and down at the intake manifold connects to the head and got nothing. I got down real close and you can hear it coming from under the intake manifold.
Any ideas what it might be?
Last edited by Ian Carr; 07-18-2007 at 08:49 PM.
#2
Burning Brakes
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Someone used to sell an attachment to a vacuum line system that placed a lit cigarette in the system and would leak the smoke wherever the problem was so you could see the leak. I thought Tim at speedforceracing.com sold it but I could not find it on his site. Might check with him to see if he has anything like that.
#4
resident n00b
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presicion imports in Nashua NH had this weird smoke machine that they used to find a vacuum leak in my friends car. Worked great. but the thing was the size of two milk crates & he said it was old & expensive/
#5
That Guy
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ringo- i tried diff ways with a cig and the vacuum system... didnt work
steve- i can easily pressurize the system, my only problem is my air compressor is high pressure- low volume. Maybe i can rig up a old boost controller to make it less pressure.
Jake- smoke machine would be a good way to do it... i just dont have one :-\
steve- i can easily pressurize the system, my only problem is my air compressor is high pressure- low volume. Maybe i can rig up a old boost controller to make it less pressure.
Jake- smoke machine would be a good way to do it... i just dont have one :-\
#6
I got the SFR cigarette tester and it works great.
Regards,
Regards,
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#8
Originally Posted by TurboX
r
steve- i can easily pressurize the system, my only problem is my air compressor is high pressure- low volume. Maybe i can rig up a old boost controller to make it less pressure.
steve- i can easily pressurize the system, my only problem is my air compressor is high pressure- low volume. Maybe i can rig up a old boost controller to make it less pressure.
#9
Burning Brakes
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#11
I had a leak under there and it came from the idle stabilizing valve, check your hoses in and out of that. Took me 3 hours to repair and sore hands and some swearing, but it was better than taking the inlet manifold off. It actually felt quite good after I tightened the last hoseclamp.
Regards
B.O
Regards
B.O
#12
I made a similar device using an old IC pipe. I blocked off one end then used the existing threaded hole to attach an air adjustment valve along with a small gauge. The vavle makes it very simple. I just plug in the air comressor and turn the valve up to the desired pressure.
#13
That Guy
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Originally Posted by boerge
I had a leak under there and it came from the idle stabilizing valve, check your hoses in and out of that. Took me 3 hours to repair and sore hands and some swearing, but it was better than taking the inlet manifold off. It actually felt quite good after I tightened the last hoseclamp.
Regards
B.O
Regards
B.O
Which hose was leaking? i am using one of the old hoses that comes off of the manifold and i think it might be that one. I might just make Sunday my "fix the
Porsche and hope it doesn't turn into a multi-day project" day
#14
My bet is the rubber seal for the vaccuum line and the brake servo booster.Pressurizing the system or the cigarette test is not going to work because of the check valve before the booster (it allowes the air in and no air out).You can fix it temporarily with silicone goop, but I would just replace it - all rubber parts which are 20 years old and exposed to high temperature are shut -period.