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Waste gate not working, what am i doing wrong?


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Hello and once again i cant get things right?... 

i have a freddy greddy intake and shown below is my vacuum diagram. I plumbed the vac line from precision turbo 38mm  wastegate directly from the intake manifold with no “T‘s” or any sharp bends or obstructions with 2 zip ties on each end. Its about 3 feet long and its plumbed exactly to the instructions diagram A. shown in the picture i did it this way As i do not have any electronic or manual boost control as its started life as a de/na rb25. 

i went for a drive and made 18 psi and the gate did not open... i put a “red” 6 psi spring... 

what the heck is going on? 

B2DC79EF-D449-4FC8-91B6-ED91C72516C5.jpeg

E5A7717D-BEBB-4941-8811-744AD4B508F1.jpeg

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First things first, do NOT hook up the boost source line from the plenum. You really really want that signal line to come from immediately after the turbo, not downstream of the throttle. The pictures tell you the best place to get it.

Second things second.....does the wastegate even move? Is it stuck? If you put compressed air on it instead, will it open? Etc.

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Damn bro, thanks for the info.... i guess i have to tap the intercooler piping right after the turbo because the compressor housing did not come with a nipple/barb. But u dont think that if the boost gauge reads 18psi from the manifold, the wastegate wwouldnt read the same and then open? I believe testing the wastegate with a compressor is the best bet... thanks 

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19 minutes ago, Dil-Dog said:

But u dont think that if the boost gauge reads 18psi from the manifold, the wastegate wwouldnt read the same and then open?

That's not the problem. The problem is that the wastegate is supposed to control the boost made by the turbo. If you connect downstream of the throttle and have the throttle partially open, there are conditions where the boost can be much higher upstream the throttle than it is supposed to be. The turbo ends up working harder (more exhaust backpressure) than it needs to. This is actually not a problem a lot of the time, but some very bizarre boost control problems sometimes happen when it is set up that way. It is far better to simply avoid it by doing it properly.

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But... yes*

In the scenario you described, it should open, barring some scenario where the vac line on the wrong side of the gate (if it has two, etc).

This is likely why GTSBoy said test it off the car to make sure it actually can open.

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Might have a split in the diaphragm. Actuators/gates only really want positive pressure. You have picked up actuator feed after throttle, giving it boost and vacuum. Picking up before throttle generally eliminates vacuum.

Feeding an actuator vacuum will try and pull the diaphragm in it the wrong way when throttle is closed, sometimes damaging or jamming them.

Boost gauge, Fuel reg and bov want boost and vacuum (after throttle), Wastegates and boost solenoids use boost only (before throttle). This is the way the factory does it for a reason.

As above need to check that your actuator works with a regulated air compressor to confirm it actually operates at all first.

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Shit... i hope not it is brand spanking new but what u are saying makes sense, i will get back to guys tmm on the progress, i know this sounds like a silly question but what is the best way to add a lil nipple/barb to the aluminium intake piping right after the turbo? 

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9 minutes ago, Dil-Dog said:

silly question but what is the best way to add a lil nipple/barb to the aluminium intake piping right after the turbo? 

Drill hole. Weld on fitting.

You can thread a fitting into a hole in a thinwall pipe....but i'ts a bit shit,  very highly recommended not to. If you are talking about aluminium casting, you should be able to tap a thread into it, but you need to be very careful about drilling and tapping swarf (ie make sure it doesn't go inside the pipework - preferably do it off the car).

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1 hour ago, Dil-Dog said:

Shit... i hope not it is brand spanking new but what u are saying makes sense, i will get back to guys tmm on the progress, i know this sounds like a silly question but what is the best way to add a lil nipple/barb to the aluminium intake piping right after the turbo? 

I just drilled and tapped into the compressor housing using grease on the drill and tap and doing a little bit at a time.

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25 minutes ago, KiwiRS4T said:

I just drilled and tapped into the compressor housing using grease on the drill and tap and doing a little bit at a time.

thats pretty ghetto, at least the intercooler will catch the big chunks!

if i was to do that, i would use a garden blower or compressor to pressurise the pipe work to shoot it back into my eyes .

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friends and family... i am A class bone head.

Upon further inspection, at the back of the wastegate there are TWO!!! Vacuum ports on the bottom on eachside so you can route a line to closet side when Its installed. I did not see it and Left it open and they even provided a blank/cap to close off the port that you are not using. 
 

An important lesson was learned today, do not smoke and then go playing mechanic on your car. It could of easily blown shit up when i made 20 psi

 

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