How to preform a Intake Track Pressure Test?

bbird94

Registered User
Hey guys,

I would ike to figure out if I have any obvious vacuum leaks and I was wondering how to correctly do this test. Do I need a certain tool kit and how do I go about it?

Let me know and thanx for all your help??!

Later,
Brandon
 
I like to use propaine..Release it and listen for an idle change..When you hear an idle change you found your location
 
Personally I have tried the propane method and It didnt work for me
What did work was pressuring up the whole intake system and using soapy water cover all the diffrent fittings, running my hands over all the fittings to feel for air escaping and listening as well. You can find every leak that way including leaks that might only show up at 10 lbs of boost. If you have any further questions you can E mail me at kenny.wagner@fleetpride.com

Ken
 
...
What did work was pressuring up the whole intake system ...

Yep, very simple to do, even I managed to do that. :) Hissing sound reveals pressure leaks quite well. In my case only sound came from around EGR valve gasket, and it was so minor (at 15psi) that I did not bother to fix it (my quess is that my EGR bolts are bit too long and therefore they do not seat 100%)

Procedure is quite simple, close your TB (count the number of rounds you have to unscrew TB adjustement screw, to easier re-adjustment..) feed slowly up to 7-15 psi to the outlet where a boost gauge line is connected and listen leak sounds.

Note that this might not reveal vacuum leaks, just boost leaks as vacuum leaks might shut down when pressure is present and other way around.
 
Like Ken says ,propane method did not work well for me either.

I use a peice of aluminum tube 2 3/4 inch diameter ,4 inchs long.

I used a flat peice of aluminum welded to the end of the tube.

I drilled & taped threads in the flat portion weld on the tube.
So I could screw a air fitting that would connect to my air
compressor hose.

Then i used the rubber hose that held my cold air intake tube
to the throttle body. I used this rubber hose to connect
the the tool I made to the throttle body to hold together.

Then you can connect your aircompressor hose to new tool.
And add air. I would set the compressor regulator to 10lbs.
Then pressurize your system,and use soap and hearing
as Ken pointed out to see or hear air leaks.

Randy
 
Well pressure leaks are one thing..propane has worked for me on vacuume leaks//Soapy water can work on easily visible areas


Now how did you manage to get 10 PSI and and check for soap bubbles is what I'd like to know!.....I can picture Ken driving with Randy sprawled across the engine looking fer lil bubbles at 50 mph..This whole story about doing it sitting still just seems to easy
 
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Now how did you manage to get 10 PSI and and check for soap bubbles is what I'd like to know!.....I can picture Ken driving with Randy sprawled across the engine looking fer lil bubbles at 50 mph..This whole story about doing it sitting still just seems to easy

You can add 5lbs or 25lbs air pressure to simulate the boost pressures
the blower will produce. you can do this while parked ,setting in your shop,
yard, or driveway.

Vacunm line leaks will show up during a test check for boost leaks.

Brandon, you should try and put a hose clamp or plastic tie on every
vacum lines ends that you can get to. this includes all vacum lines,
on the intake side of your induction system as well as the boost side
of your induction system, & PCV valve lines ends..

Your Vacunm hoses are old. they may look great ,feel great.
But can count on that you have some seapage with old rubber lines.
Get 6 to 8, 3/8 to 1/2 inch hose clamps use the metal clamps
on the boost side of your indution system rubber lines, Plastic
ties work very well on the vacumn lines, before the supercharger
side of your induction system.

Propane will show large leaks, but propane will not show small
seapage leaks well.

Clamps and plastic ties are cheap, you can install them in a few minutes.
do me a favor and try this out asap as you can. and then get back
to use on this post with the outcome of spending $5.00 on clamps
and plastic tie 30 minute installation.

Ken And I have fabed parts of are intake systems. So we need to do
a pressure check on the complete induction system to sometimes check
are work out. And i run can run up the 25 to 30 pounds of boost.same
with Ken setup. So we needed to build a tool to pressurize are custom
induction systems. and we both know if we run high boost the silicon
hose connection will not leak or blow off.

So I do not think you need tool fab a tool like we use. To pressurize
the complete induction system. Just inspect and clamp or plastic tie
every vac and boost line you can get to. Your car will run better
if you do this.

But clamping all the boost and vac line may not fix your problem.
but you will know this will never be a problem again.after clamping
all your lines,and you still have problem . Them check for IC tubes
for leaks and reseal if needed.

Hope this helps ya some Randy
 
Well pressure leaks are one thing..propane has worked for me on vacuume leaks//Soapy water can work on easily visible areas


Now how did you manage to get 10 PSI and and check for soap bubbles is what I'd like to know!.....I can picture Ken driving with Randy sprawled across the engine looking fer lil bubbles at 50 mph..This whole story about doing it sitting still just seems to easy


Damon....Are you feeling OK:rolleyes:

Ken
 
Actually I built about a dozen pressure testers for Victor. They have a regulator on them and they just clamp on the intake tube. Hook it up and set the pressure and you can walk around checking for leaks. I dont know if he has any left. I had the most annoying idle on the car and after identifing all the small leaks it idled perfectly. I also found that at as little as 4 lbs my IC hoses leak passed the clamps. At 10 lbs it would blow your hat off. You cant find those kind of leaks with out mimicking the boost at WOT. I pressure test all my connections at 20 lbs of boost so know I am not leaking when the M112 starts screaming

Ken
 
Another way is to unscrew the ACT sensor, then screw in a 3/8 NPT elbow and use a quick-change air adapter with 3/8 npt threads into it. Then just use some soapy water to check for leaks.
 
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Similar to randy and kens method i have used something like this:
http://www.anver.com/document/vacuum components/vacuum generators/pumps-msp-am.htm
to create a vacuum in the intake track to reveal leaks that may occur more readily under vacuum than under boost or vice versa. These vacuum pumps work right off the compressed air, so it's a quick switch from vacuum to boost and back. I typically try to place the vacuum pump in the body of the carm or in a box, or outside the garage since it vents to atmosphere and may make listening for leaks from the motor a little difficult.
 
Actually I built about a dozen pressure testers for Victor. They have a regulator on them and they just clamp on the intake tube. Hook it up and set the pressure and you can walk around checking for leaks. I dont know if he has any left. I had the most annoying idle on the car and after identifing all the small leaks it idled perfectly. I also found that at as little as 4 lbs my IC hoses leak passed the clamps. At 10 lbs it would blow your hat off. You cant find those kind of leaks with out mimicking the boost at WOT. I pressure test all my connections at 20 lbs of boost so know I am not leaking when the M112 starts screaming

Ken

I bought one of these from Victor and thought it was pretty neat. I immediately found a really bad leak around an injector port into the head. If you are the type that always seems to be taking apart things on your engine to fix, upgrade, etc., this little doodad is indispensible.

91supacoop, how much do one of those vacuum pumps go for?
 
No I'm not Ken.....:O)

Im glad for that Damon

The vacuum tester is a good idea as well. I would bet that 80 to 90% of SC owners when doing repairs or mods dont check, in any form, whether they have a leak or not. If you think about it, all the bucks paid for mods and repairs and most people just cross their fingers and hope or assume they have everything sealed.

Ken
 
Now how did you manage to get 10 PSI and and check for soap bubbles is what I'd like to know!.....I can picture Ken driving with Randy sprawled across the engine looking fer lil bubbles at 50 mph..This whole story about doing it sitting still just seems to easy

What amount of beer would be needed for this to actually happen? :p
 
troubles

hey guy im having the same problem but my smoke is blue the car runs rough and it don't sound like it firing on all cylinders it falls on its face no power i just reacently replaced the head gaskets it ran better with a blown head gasket any help would greatly be appreciated
 
reply

it does it all the time i had the heads redone by a repital machine shop it act like it running rich the fumes burn my eyes and it falls on it face rough idle no power the heads checked out fine they were milled i had a valve job don on them the whole works please i really need some help im getting fustrated i want my baby back i would hate to have to get rid of it
 
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