sr20 low vacuum issues

[240sr20de t]

when i start my car the vacuum is at about 5mg but sounds like is about to stall but when it warms up it goes to 10 instead of 20 i checked all my intercooler piping and no vacuum leaks am i missing something or is this normal?

[koukimuncher]

i have a the same issue i checked mines thoroughly and still does the same shit and i think my starter is about to go dead

[240sr20de t]

anyone??? could it be the intake manifold ? or the collector gasket? or some other thing? any ideas

[blksylv]

have you compression checked the motor? is the timing set correctly?

[240sr20de t]

i havent checked my compression but will it affect my low vaccum issue ? sorry for the question im a newbie here but the timing was checked by a friend who happnes to be a mechanic but that was it .

[240sr20de t]

could it be the iacv?

[godsmack]

it could be the iacv. just unplug it while it's idling and if something changes then you got a problem elsewhere. if you do then i'd spray brake cleaner over intake and all hook-ups and if it causes it to stall then you got a leak wherever you just sprayed. just some things for you to try

[240sr20de t]

should i unplug the two conectors or just one? i guess im going to try the brake cleaner

[ShadowMan]

Pressure test your entire intercooler system, it'll be more precise than spraying a can of brake cleaner or whatever you use everywhere. And with the motor off you'll be able to find multiple leaks at once.

[240sr20de t]

i did that but only with the intercooler piping and intercooler should i try and do it with the intake manifold too?

[godsmack]

do you have your bov recirculated?

[steve shadows]

Yeah do a pressure test it's not that hard to do you can craft a pressure tester yourself using some PVC pipe rubber coupler and a bike inflation valve and hook it up to the front of your turbo. The other way is this one...amazing and worth the investment if you plan on having more turbo cars or racing etc:

Smoke Leak Detection OTC 6525 OTC6525 OTC TOOLS 6525 - LeakMaster EVAP Tester & Smoke Machine (http://www.ntxtools.com/network-tool-warehouse/OTC-6525-p-OTC0101.html)

You can find versions for less than 1400 bucks lol but this is literally the end all be all in leak down and testing for the vacuum system...love having it around at the shop when we do end up doing dyno session for peeps.

Another possibility is one of your actual gauges is leaking i.e the actual boost gauge if you're using a cheap mechanical one...Check the bottom of the throttle body, also the bov if it's a crap blitz one these leak too. Good luck!

[240sr20de t]

do you have your bov recirculated?
no i dont have it recirculated but i did a leak test while the car was off and the bov started leaking that is not normal is it?

[godsmack]

what pressure was it leaking at? if it was a small amount no not normal. if you had like 50psi in there than yes. not sure what bov you have or what spring is in it.

[240sr20de t]

Yeah do a pressure test it's not that hard to do you can craft a pressure tester yourself using some PVC pipe rubber coupler and a bike inflation valve and hook it up to the front of your turbo. The other way is this one...amazing and worth the investment if you plan on having more turbo cars or racing etc:

Smoke Leak Detection OTC 6525 OTC6525 OTC TOOLS 6525 - LeakMaster EVAP Tester & Smoke Machine (http://www.ntxtools.com/network-tool-warehouse/OTC-6525-p-OTC0101.html)

You can find versions for less than 1400 bucks lol but this is literally the end all be all in leak down and testing for the vacuum system...love having it around at the shop when we do end up doing dyno session for peeps.

Another possibility is one of your actual gauges is leaking i.e the actual boost gauge if you're using a cheap mechanical one...Check the bottom of the throttle body, also the bov if it's a crap blitz one these leak too. Good luck!
i have a hks bov but it is an old one and it was leaking when i did the leak test but with the car off ?? idk if its normal but ihave a autometer mechanical one do you think it is actually leaking form there? that smoke machine looks good but is too expensive i prefer to buy a bigger turbo lol

[240sr20de t]

what pressure was it leaking at? if it was a small amount no not normal. if you had like 50psi in there than yes. not sure what bov you have or what spring is in it.

no it was leaking as soon at it began to pressurize so i guess this is not normal. i have an hks but an old one i didnt want to change it because iwasnt sure if this was normal

[godsmack]

change it. it shouldn't be opening until somewhere around 14psi IIRC. another problem that I saw happen is a coupler ripped a real little bit and would leak at first but when the hot air would get to it after a little it would swell and seal shut decently. but i would go with the bov being the problem. got an idea to check it not sure if it will work but pull the vacuum line off the bov then plug it and wrap a bag around the bov and seal it. start the car and see if the bag fills up with air.

[240sr20de t]

so the bov is supposed to be closed when the car is off ? so what whoud i do ? because i actually feel and hear the air coming out so if it is not supposed to do that then it is my bov! and about that bag theory if i start up my car wont it vacuum it?

[godsmack]

yes it should be closed while the car is off. and when the car is on and that's leaking then the bag will fill up with air from the intercooler piping. if it's not leaking nothing will happen and you're problem is elsewhere.

[godsmack]

http://upload.wikimedia.org/wikipedia/commons/5/56/Throttle_body_openBOV12.jpg