Im having strange boost problems. I have a lot of preload on my arm (about 9mm) and im running 12psi of boost. I turned up the boost using a bleed valve a quater of a turn and it's hitting 21 psi. I thought the bleed valve was at fault so i removed this and run standard actuator pressure. Its now 10 psi.

I have nothing inbertween 12 and 21 psi.

 

9mm of preload is far too much. Get an actuator more capable of what your trying to do.

 

It was only loaded with the 9mm to get the 12psi. I understand it should be something around 6mm preload with a aftermarket I/C. The -31 isn't that old but i guess even newish stuff can fail.

 

depends on the make of the -31 actuator.
genuine garrett should be good for a couple of years, collins and the like tend to have weaker springs that lose their ability over time.
call to matt lewis will get you a new one though.

 

is your amal valve plugged in and working?

 

sorry i didnt explain. Im running megasquirt EFI. Im going to fit another garrett -31 and see if its that.

 

You have answered your own question... Bleed valve is faulty or just extremely sensitive!
Without it you will only make actuator preload pressure, as you are.
I dont know why Stu suggested another actuator as it is doing exactly what it's supposed to if it's holding 10psi without problems?! lol