[OpenFlash]

Originally Posted by PlutoniumTans

After installing intake my car started overboosting !!!! wtf can that be ? overboosting hard body !

Those vacuum lines provide vacuum to close the wastegates. Can't see how you could have gotten more signal line vacuum unless you hooked them up to the solenoid incorrectly (ie bypassin the solenoid completely). Which would be unlikely if all you did was install an intake.

[BobS]

Originally Posted by shiv@vishnu

Those vacuum lines provide vacuum to close the wastegates. Can't see how you could have gotten more signal line vacuum unless you hooked them up to the solenoid incorrectly (ie bypassin the solenoid completely). Which would be unlikely if all you did was install an intake.

Shiv, how to you test if the vacuum lines are working properly? If i have someone rev the car and listen, should i hear something?

[PlutoniumTans]

Originally Posted by shiv@vishnu

Those vacuum lines provide vacuum to close the wastegates. Can't see how you could have gotten more signal line vacuum unless you hooked them up to the solenoid incorrectly (ie bypassin the solenoid completely). Which would be unlikely if all you did was install an intake.

Funny thing is I got both, I got the underboost code, but I also got the overboost code and and go into a limp mode, as if my wastegate is shut closed or something. Very frustrating I must say

[OpenFlash]

Originally Posted by BobS

Shiv, how to you test if the vacuum lines are working properly? If i have someone rev the car and listen, should i hear something?

What I do is move the wastegate position setting in the Procede software around and watch the wg and make sure they respond immediately/quickly. If they transition slowly from position to position (or not at all), you likely have a vacuum leak or some other wg related issue. I've even seen the c-clip on one of the wg fall off and not move around at all. In your case, the best you could do is hook up a vacuum gauge to your vacuum canister and confirm that they are pulling 20+ " of vacuum.

[OpenFlash]

Originally Posted by PlutoniumTans

Funny thing is I got both, I got the underboost code, but I also got the overboost code and and go into a limp mode, as if my wastegate is shut closed or something. Very frustrating I must say

Mods?

[PlutoniumTans]

Originally Posted by shiv@vishnu

Mods?

I was running fbo+meth on jb4, I replaced dci with Dinan intake and went for a spin, the car felt very aggressive after installing it, and then it would stumble as the charge pipe popped of or something , and looking at the boost gauge and logs it would go above 20 psi in a matter of a second, the car made boost very easy, just barely feathering the pedal boost would go over 10 15 psi. The codes i got were
2F8F Accelerator pedal module and brake pedal, plausibility
29F4 Catalytic converter conversion
29F5 Catalytic converter conversion 2
30FE Boost over target
3100 low boost mode engaged -- CEL displayed
Car still goes into limp mode under hard acceleration. I've had an overboost issue similar to that upon testing the very 1st DIC maps with v5, the dealership stated they've fixed the problem by replacing the boost pressure sensor, the fix wasn't for long.

[vasillalov]

I am not surprised at all. I've had similar problems with vacuum lines going brittle and eventually cracking in almost any car that I've owned. The OEM vacuum lines are not very good for longevity. I've learned to check/replace all vacuum lines every 2 years or upgrade to 2-ply or 3-ply silicone braided hoses whenever possible. If you are replacing those hoses with non-OEM items, make sure the replacements are properly rated to withstand the vacuum inside. The last thing you want to do is put spongy lines which will crumple under vacuum.

Just my $0.02

[PlutoniumTans]

Originally Posted by vasillalov

I am not surprised at all. I've had similar problems with vacuum lines going brittle and eventually cracking in almost any car that I've owned. The OEM vacuum lines are not very good for longevity. I've learned to check/replace all vacuum lines every 2 years or upgrade to 2-ply or 3-ply silicone braided hoses whenever possible. If you are replacing those hoses with non-OEM items, make sure the replacements are properly rated to withstand the vacuum inside. The last thing you want to do is put spongy lines which will crumple under vacuum.

Just my $0.02

How do I know which are good ?

[vasillalov]

Originally Posted by PlutoniumTans

How do I know which are good ?

You can either test each line individually, but at this point, why bother testing, when you can just replace it.

I usually buy vacuum line in bulk: say 20 ft spool of various diameters. Why bother spending time testing a line. Just replace it every 2 years and don't worry about it.

Another thing: those braided lines sometimes can hide a tiny crack in them under the fabric shielding. You don't necessarily see it but its there.

I've solved ton's of poor idle-in issues on my previous cars by simply replacing the vacuum lines.

As a side note: I am actually glad that the N54 does not have a dip stick. My last car had a cracked dip stick tube at the base where it connected to the oil pan. Very difficult to spot, but it was the root of poor idleing of the engine.

So yeah, vacuum lines = important maintenance item in my book.

[PlutoniumTans]

yeah I'm gonna go to NAPA tomorrow and buy some line and just replace it, delete all the codes and see if it's going to help

[vasillalov]

Originally Posted by PlutoniumTans

yeah I'm gonna go to NAPA tomorrow and buy some line and just replace it, delete all the codes and see if it's going to help

Make sure you get the correct internal diameter... Go for either 2-ply or 3-ply silicone ones. Alternatively, you can try online sites like these:

http://www.hiperformancestore.com/

http://www.mcmaster.com/ -> has some nice abrasion resistant 2-ply vacuum hoses.

[PlutoniumTans]

Originally Posted by vasillalov

Make sure you get the correct internal diameter... Go for either 2-ply or 3-ply silicone ones. Alternatively, you can try online sites like these:

http://www.hiperformancestore.com/

http://www.mcmaster.com/ -> has some nice abrasion resistant 2-ply vacuum hoses.

Thanks man I really appreciate it =]

[Jeff@TopGearSolutions]

Yea if your running into that kind of problem replace them all. There are also some under the engine cover that go bad and nobody ever notices them. They go to those 2 black boost tanks on the passenger side I believe.

[PlutoniumTans]

Originally Posted by Jeff@topgearsolutions

Yea if your running into that kind of problem replace them all. There are also some under the engine cover that go bad and nobody ever notices them. They go to those 2 black boost tanks on the passenger side I believe.

Thanks I appreciate it, btw got my $ gotta place an order with you, just want to figure this problem 1st.

[AKG]

I had the same problem a couple of months ago, took the dealer like 4 days to figure out! and like $200... so from this thread and experience I see it's a most to check often!!! great post..

[Simple5]

Happened to me as well. My symptoms were:
1) Half Engine Light
2) Only boosting at 3-4psi on JB3 Map 3
3) Installed JB4 and found the code to be 30FF
4) Popped off bumper and re-installed intercooler (passenger side had oil coming out of the pipe where it met the intercooler and cleaned it all out.
5) Drove the car around but NO BOOST AT ALL. Feared it was a blown turbo.
6) Found one of the vacuum lines had split in half and blown off. The one directly beneath it was going to go as well.
7) Bought the same kind of hose as the OP and replaced both.
8) Now car boosts perfectly and I can enjoy my JB4.

[JunkStory]

Originally Posted by vasillalov

You can either test each line individually, but at this point, why bother testing, when you can just replace it.

I usually buy vacuum line in bulk: say 20 ft spool of various diameters. Why bother spending time testing a line. Just replace it every 2 years and don't worry about it.

Another thing: those braided lines sometimes can hide a tiny crack in them under the fabric shielding. You don't necessarily see it but its there.

I've solved ton's of poor idle-in issues on my previous cars by simply replacing the vacuum lines.

As a side note: I am actually glad that the N54 does not have a dip stick. My last car had a cracked dip stick tube at the base where it connected to the oil pan. Very difficult to spot, but it was the root of poor idleing of the engine.

So yeah, vacuum lines = important maintenance item in my book.

Originally Posted by Jeff@topgearsolutions

Yea if your running into that kind of problem replace them all. There are also some under the engine cover that go bad and nobody ever notices them. They go to those 2 black boost tanks on the passenger side I believe.

Are all the vacuum lines the ones with a fabric wrapping? I'd love to start inspecting/replacing the lines but there are so many hoses/wires I honestly don't know what is what.

[mattsfeir]

Some have the wrapping, some do not. You can follow them from the 2 black plastic vacuum canisters in the front passenger corner of the engine bay. Once the engine cover is off, it's easier to see/feel where they go.

[sdstatestud88]

What is the correct internal diameter to buy for these vacuum lines?

[._.]

3.5mm

[UltraRacer13]

OK- I took the OP's advice and blew into the vacuum hose after popping off the blue thing. I was able to blow into it without it "stopping" or reaching a full point, so the air was escaping somewhere. Does that mean I have a leak or not? Thanks. I am getting 30FC code. "Exhaust fume turbocharger, Density" which is related to waste gates.

[Simple5]

Originally Posted by UltraRacer13

OK- I took the OP's advice and blew into the vacuum hose after popping off the blue thing. I was able to blow into it without it "stopping" or reaching a full point, so the air was escaping somewhere. Does that mean I have a leak or not? Thanks. I am getting 30FC code. "Exhaust fume turbocharger, Density" which is related to waste gates.

Check all your lines. The braided ones as well. AT first glance it looked like everything was fine it took my buddy's eagle eyes to spot it.