Long story but will short it - my car has no boost or very very low in low revs (in 3000 - 5 psi, 4000 - 10psi), with peak at 5500 rpm and 14.5 psi, at 6720 12 psi. Car is re-mapped because requested pressure is 21.5 psi _ bought it like it is now.
Tried new N75, MAF, done leak test up to 15 psi -no leaks ..... no change.

Anyway I have decided to test again my DV. I pushed the piston of the valve upwards against the spring (it moved without restriction). Then with the piston pushed fully up, with the spring compressed, I placed my finger over the top nipple to form a
seal. see photo 1

Then I released the piston, keeping my finger in place but piston moved about 5 mm down - see photo 2

After I removed my finger from the nipple, at which point the piston travelled another 2 mm back and made noise (shoot).

Here is re-assembled DV - I don't know what type is it - it was on the car when I bought it.

I have tested it maybe 10 times with same result. Dost it working properly or is it faulty?

 

the piston will never stay perfectly because the spring is pushing it down and air is compressible. this test is just to test the seals on the piston if they were bad it wouldn't just drop 5mm and stop it would slowly or quickly drop the entire way. also it could drop the entire way if your finger was not over the nipple at the top of the valve.

 

Regardless, I would try another diverter valve. See if there's a audi/VW enthusiast on these forums that lives in your area.

 

I did this test to my Forge 007 and when i release the piston it will move slightly down a little and then hold until i remove my figure on top. So i think what you are seeing is normal.

 

Thanks for reply to all of you, so I need to look for something else what is wrong.