Vacuum leak, or?

ItAintRodKnock

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01GolfTDi
So, i just got a Mityvac from haborfreight(for$32) and wanted to test my actuator adjustment mostly. I decided, before I pull the panzer plate(if i do that) I'd do a simple test to see if I have a Vac Leak.

So, i disconnected the vacuum line at the Vacuum Ball and used an adapter to mount the Mityvac onto the hose, in the balls place.. I pumped it up(or down) to 20 inches and stepped away for a 5 minutes.

In that time it went from 20" down to 13" on the Mityvac gauge.

Is this indicative of a Vac Leak, or is this typical bleedoff by the system?
Vac lines are only afew months old, but all other components in the system are old as heck.
 

JETaah

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Try the same test on the mityvac with just just the attached hose plugged. Maybe the release valve on the mityvac isn't that tight. The ball should hold the vacuum but if it took five minutes to drop 7inches it probably won't affect the operation that much. If it took 5 seconds to drop to 13 inches and stayed there then it might be an issue.
 
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flee

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I think he connected the MityVac to the hose instead (in place) of the vacuum ball.
So, checking the whole system I would expect to see some loss through the pump, at least.
Not a big deal, IMO.
 

ItAintRodKnock

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Thought about it being the valve on the mityvac too. I'll look at that when I am actually doing the actuator rod. Also, the fact it didnt go to zero was comforting.

Yep, it was in place of the ball; meaning, instead of the V.ball connected to the hose, I plugged the mityvac onto the hose to provide vacuum to the entire system, as opposed to testing the ball itself.

Sent from my VS987 using Tapatalk
 

JETaah

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mi 48836
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Flee is right.
I think I read your post wrong. I thought you were testing the ball itself in your first post.
I have to mention that if there was a hole in the turbo actuator you could well have all kinds of debris throughout the vacuum system...aside of the branch that leads to the vacuum ball. The hole in the actuator or elsewhere in the system is a constant draft all the way into the upper cylinder head where the pump dumps system air from the vacuum supply side. I have seen rust and other dusty debris completely clogging the N75, the black/white check valve, and the brake booster check valve small nipple disabling the turbo and EGR works. Also, the debris can prop open the b/w check valve and cause problems. I don't know if the N75 small nipple provides a solid seal when the engine is off. The turbo actuator, EGR and ASV diaphrams vent to atmosphere when the engine is off through their respective control valves.
 
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wonneber

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Do the test again but wiggle the big fitting on the vacuum pump to see how loose it is and how fast the vacuum drops.
Mine went down pretty quick.

Some fix it with epoxy, silicon sealer, and/or peening the metal around the fitting.
Silicon lasted a little while for me, epoxy longer.

BTW. What are you trying to diagnose?
 
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