Decided to do a random boost leak test today (always a good idea) and noticed i have air coming out of my PCV line thats supposed to go to the turbo (not the one on the intake)

theres no holes in the line or anything, it just leaks out and escapes through my intake, so when i boost leak test my system, it slowly bleeds down because of that.

is this normal? i managed to find a few small leaks with my vaccum lines but no other issues. pressure bleeds off kinda fast from the pcv line tho.

Just making sure everything is ok.

 

It's best if you boost leak test after turbo, not Pre.
Edit
That's strange about the line itself. I've not noticed that on my car.
If the line isn't being rerouted to the turbo or intake can't you just plug it?
I think some one else with a efr had a question about that.

Side note I do recall suxost having this issue with the stock k04.
Dealership tried all kinds of things to fix it with no results. His car is still fine.
As long as you have proper compression in those pistons I don't see a problem.

 

Hey Dart, did you notice any change on your gauge indictaing a vacuum or boost leak?
I need to check my vacuum line and see because it doesnt seem to idle at the same points anymore.

 

When I do it, I usually take off my SRI and hook the boost leak tester coupler directly to the intake side of the turbo. By doing that, the back PCV line won't leak air out since it's after where the coupler is connected. It'll also help you determine if you've got bad turbo seals or a PCV valve / check valve issue on the front line on the intake.

 

No everything seems normal. Car idles about -18.5 in/hg and I get -20 when I let off the gas while cruising.

 

I had to tap my intake for the pcv since im not on the stock turbo.

 

Ooooh ok. Hmmm. Well, how well if your intake clamped? Perhaps you could try that?

 

I've been trying to test mine post turbo, starting at the upper charge pipe, but I can't get over 10 psi due to it bleeding off. I removed the oil cap when I did it and I felt like it was bleeding from there. I plugged it just out of curiosity and something near the intake made a nasty croaking sound so I quickly removed it. I'm using a cheap tire inflator compressor, so my problem might just be needing a better compressor lol.

 

Yeah, the air seeps past the rings, goes into the crankcase, and then out the oil cap and/or the back PCV hose.

 

Luckily that was the only place air was coming from. Found some tiny leaks in my vacuum lines and fixed them.

 

How much pressure do you put through the turbo when testing?

 

I usually test it up to a few PSI above where I'd run it. If I'm running say 23psi, I'd probably test it up to say 26 or 27 to make sure. The reason I do that is when the car is running and/or in boost, there's more than simply air pressure in the piping, there's also airflow going through the piping at speed, so that can affect it a bit.

 

I understand you logic and agree but, I have been informed a few time that pressurizing from turbo inlet is a big no no with anything over 5-10 psi. I would think the compressors seals should stand up to the pressure but everyone's says no.

 

Okay, well they somehow stand up to boost pressure, tens of thousands RPM, and hundreds of degrees while you're doing your thing with the car on, so I guess I don't understand that. Do they make the case that pressure doesn't start until later in the housing?... because I don't think that'd be the case when you let off and the bypass has to open (which is right at the mouth of the inlet too, by the way)...

I'm fine being told I'm wrong in the interest of the betterment of knowledge, but if everybody does use the charge piping then everybody would have the be reporting the same pressure loss through the PCV system problem too.

 

The reason people say not to connect a boost leak tester to the intake side of the turbo to boost leak test it is because theres no oil feeding to it to keep it lubricated but then again your not doing it for hours upon end so im sure it wouldnt be to bad..thats the reason i heard most people dont do it

 

I have tested at the intake side of the turbo, before. That's the best way to test for a BPV leak. It's just that you are spinning the turbo with no oil, which is fine if it's cool and you're not doing it for long. The issue I had is that the PCV line that goes to the valve cover from the turbo caused me to lose most of my boost-test pressure so I had to crank up the pressure on my air compressor. I didn't put anything about he pre-turbo testing in my write-up because I didn't want anyone telling me I caused them to ruin their turbo.

 

It's not like you're actually building a lot or pressure in the turbo. You set the pressure on your compressor regulator to say, 30 psi, but your turbo has a PCV line going into the valve cover that bleeds off a lot of that pressure into the valve cover. You've removed your oil filler cap, so that pressure is escaping. It's not like we're shooting 30 psi into a closed system.