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BBV blocking boost?

Bluemagic

Bluemagic

New member
Ok i first suspected tht I had a vacuum leak. I did. Fixed it and I still have low boost. 3.3 -4.3 I believe.

Now the bbv is stopping boost. Took lines off and instantly got full boost Lol. How can I resolve this? Do I need a new BBV?
 


Local junkyard...go yank a bunch of them off...have you done a carb cleaner check to make sure its not a vac leak?
 
Water?

LOL, no.

CARB CLEANER.

Spray it around while the car is idling. If the idle surges, jumps up or it almost kills the car...then you've found your leak...follow the blower, LIM, TB, vac lines, fuel injectors, etc...all that crap.

And you have to unplug it, then remove the 3, 10mm bolts from the blower that hold it in...it is worlds easier with the supercharger off the car though...so, expect a few hours ****ing around.
 


Before replacing it, I would try and spray some PB Blaster on the shaft of the BBV and work it in. It may just be getting hung up.
 
Yea I tried that to no avail. I'm leaning toward a vac leak though even though I'm reading 19 vacuum at idle. Just changed the spark plug wires and now no boost. Bbv couldn't have just died
 
Are you sure you got the plug wires on there right? lol...


2 4 6
ENGINE
1 3 5

^^YOU STANDING IN FRONT

Coils go from top to bottom:

6
3
2
5
4
1
 
Haven't tried holding the shaft yet. I'll try that in a bit. Just hold the shaft in bbv and have someone apply the gas?

Also hmmmm I'll check the wires ASAP lol. I thought me changing them one by one would help lol. I'll double check.
 


Happened to me two weeks ago. 4 psi at WOT. I got a bbv from the junk yard and I have full boost again. They can just go bad.
 


Ok plugs are correct, tried carb cleaner no idle changes. I have a question though does the shaft for the bbv disappear Into the bbv or does it stick out halfway at idle? Mines doesn't fully retract into the bbv here is a pic
daf8583a.jpg


This is how it sits with the car off
6fac4b99.jpg
 
that's right. the butterfly is open at idle. if you rev it you should see it move down a little, but not fully close.

it'll only fully close once you actually get into boost.
 
Ok great, also the shaft trick, if someone holds it and I see full boost then what's next? Or I don't see a change in boost then what?
 
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