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Boost Struggles To Go Past 2psi

aquariuz6
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aquariuz6 Proficient

aquariuz6

Posted
Posted

Hi guys I was wondering if you guys can give me a hand on this one. As this has totally got me stomped.

Ever since I got my FMIC installed my boost won't go past 2psi.

I have checked all connections and there is no leak. But I can still hear an air leak somewhere.

I totally have no clue where it is coming from.

Does anyone have any ideas to what things I would need to check?

I have been told to check all air linked things. Besides the FMIC connections is there any other things that I should check?

Cheers

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https://www.sau.com.au/forums/topic/167463-boost-struggles-to-go-past-2psi/
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jeffworld2 Veteran

jeffworld2

Posted
Posted

just tighten everything, it may not leak under vacum (idle) but will on boost. it sounds pretty bad if its only hitting 2 psi, perhaps your gauge is stuffed or getting a signal from the charcoal canister or something. if it feels slow then obviously this is not the case .

even the wastegate should hold it at at least 6

aquariuz6 Proficient

aquariuz6

Posted
  • Author
Posted

When I rev the car on idle I can see the wastegate opening up.

So that shouldnt be a turbo problem.

Acceleration is very poor as if its struggling.

If I put soapy water over it, wouldnt it just suck it in? not blow it out as bubbles?

paulr33 Grand Master

paulr33

Posted
Posted

the leak will be big enough to see/hear it wont be a little fine leak i wouldnt expect

the gate shouldnt open at idle or shouldnt have enough load to open at idle

sounds like the gate might be stuck open, this would explain laggy operation and jack all boost

have u ever had that issue before? strange that u would notice it all of a sudden

MBS206 Grand Master

MBS206

Posted
Posted

Wastegate sounds to be stuck open, or opening WAY too early

Check you connections for the actuator etc, as others have said, it should NOT be opening at idle.

Also check that you have nothing INSIDE the pipes.

New pipes/intercoolers often come with packaging in them.

GTR1993 Mentor

GTR1993

Posted
Posted (edited)

oops my mistake, almost completly off.

What happened was the T clamp wasnt done up, i run abour 24 psi boost so it pushed it off and i run map sensor so the car ran fine with massive leaks. The silicone was just still touching around the intercooler inlet as it couldnt come off completly as the body of the car held it on.

on another note does the car splutter as it should run rich as with such a large boost leak if its AFM base computer

Edited by GTR1993
Green_s13 Proficient

Green_s13

Posted
Posted

it sounds like your wastegate is stuffed if you had a leak that bad from the intercooler your car would be running like a dog would be very rich and wouldn't idle well. the other thing is there could be some stuffed up one of the pipes not the first time that has happened

aquariuz6 Proficient

aquariuz6

Posted
  • Author
Posted

The wastegate opens up only when I rev the car at idle.

So I should check the pipes on the intercooler to make sure theres nothing stuck inside.

Could it be something to do with boost controller by any chance?

paulr33 Grand Master

paulr33

Posted
Posted

are u sure you are thinking of the same thing? i think you are confused

what is the "wastegate opening" how are u measuring if its opening?

what does it look like? does it make a sound? i think you are thinking of the stock bov noise

blind_elk Grand Master

blind_elk

Posted
Posted

You shouldn't be able to produce boost when you free-rev the engine. There is no load to create enough exhaust gas to turn the turbine to create the boost. If the wastegate is opening under this situation, then the wastegate is kaput.

aquariuz6 Proficient

aquariuz6

Posted
  • Author
Posted

So how do I fix that? Its just the stock turbo?

Even my other turbo (highflow) didnt want to go past 2psi so I put the stock one back on.

Both turbo's did the same thing... I don't think both wastegates are screwed.

I do notice that while driving, under load (when the boost builds up) it releases and makes a hissing sound.

Couldn't this be more on the actuator because it was used on both turbo's to get the same result

B-Man Grand Master

B-Man

Posted
Posted

Wastegate is activated by boost pressure and most often lots more than 2PSI. As others have said , you shouldn't be getting any boost by free revving. You should have mentioned that your other turbo did the same thing before.

How are you measuring boost ? U sure the guage is working OK ?

If your wastegate is opening under free revving conditions - this may indicate a blockage somewhere between turbo and cooler/throttle body.Is the car hard to start ?

Where is your boost gauge plumbed in ?

Sounds very strange to me.

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