Car will not make boost. Need some help

Sprayer84

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Me too man. I've about had it with this thing. I was thinking though. Is it possible that my BOV is not staying closed? It should be open under vacuum and close as the vacuum dissipates correct?
 

GB10

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Do you have the top port on the wg vented to atmosphere? BOV vacuum line ran from intake manifold to top port on BOV(if it has two ports)?

BOV should be open at idle/part throttle and closed at wot. Try and test the wastegate diaphragm with a vacuum pump to ensure it isn't blown apart. Hook a vacuum pump to the top or bottom port and see if it leaks.
 

Sprayer84

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Do you have the top port on the wg vented to atmosphere? BOV vacuum line ran from intake manifold to top port on BOV(if it has two ports)?

BOV should be open at idle/part throttle and closed at wot. Try and test the wastegate diaphragm with a vacuum pump to ensure it isn't blown apart. Hook a vacuum pump to the top or bottom port and see if it leaks.


Just put my vacuum pump on it. The top
wastegate port will hold 20" of vacuum all day. The lower port will not hold any
 
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Sprayer84

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yrutamu3.jpg


Is that the large yellow 10psi spring? Diaphragm does not appear to be torn
 

one eyed willy

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Makdaddy

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If the wastegate is unhooked from both ports and the compressor port is blocked it will build about 8psi.

That would be expected the spring is about 8lbs.

If the compressor port in run to the top of the wastegate with the bottom port open it goes as high as you'll let it. Smoke test didn't reveal any leaks

That would also be expected as Pressure from the turbo compressor side will not let the spring release

So it sounds like the WG is working correctly
 
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mikeyfitz

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That looks like the small yellow spring which would only be 3#


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Sprayer84

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Seems kinda off but it's building boost. I'm going to try and do a leak test in a bit. See if anything else is going on
 

Makdaddy

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The first time you took the gate apart and found the yellow spring , did you put it back together and install it?

If so did you get the same results? I assume.

Or did you only reinstall when you changed the green spring for the yellow?
And know it appears to be working better somewhat
 
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