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hai guise, was wondering if there are any home tricks to checking the state of the intake? IE if there are any air leaks?

or do i need to take the car to a shop for them to pressure test it?

cheers

Edited by Clutch
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https://www.sau.com.au/forums/topic/351535-intake-leak-test/
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I made up a cheap one with some pvc pipe caps and a $20 hand pump. See below photos. I blocked off the pipe going into the throttle body, hooked up the pump to where the pod filter was and pumped away.

The advantage of the hand pump over an air compressor is that because it is quiet it is very easy to hear even the smallest leak.

Do you mean the intake manifold or intake piping? Mine was for the intake piping.

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If you get a can of Aerostart or similar and spray it around while the car is idling it should raise the revs if theres a leak as it will suck it in. Perhaps not as good as the method mentioned above but if your looking to do it without spending to much that would be the the way to go

To check for a leak in intercooler, piping or around silicon joins, etc spray with soapy water, preferably while at a high idle (1500-2000rpm is plenty).

If you have a leak it will blow bubbles.

Seems wierd & you may think the water would get sucked in but it works...

Another good one is to remove your pod / airbox so you have access to the afm and while the car is idling cover the afm with your hand so no air can get in.

Then you should be able to hear the hiss of where the air is getting into the intake.

if you have a leak as well, you should blow a small amount of black smoke on boost. some of the air will escape the intake piping, but since it's still being measured by the AFM the correct amount of fuel will be going in as though there wasn't a leak.

Unless you're running a MAP sensor like me. then you're screwed for this idea lol

yes. If the leak is big enough in your case, you'll be sucking in air that hasn't been measures by the AFM while idling or off-boost. This will cause you to run lean, and missfire like a 14yr old boy at a wet T-shirt comp.

Damn you!

I read this thread a couple of hours ago and thought hmmm maybe i'll go look over my intake to see if I have any leaks. Turns out I have a leak coming from under the plenum where the damn gasket has slightly blown out.

God damnit!

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