turbo kraut

so i went out and got an el-cheapo till the podi is made(i am planning on getting the borg guage or something better with it)



but i got a equassian or whatever from o'riellies



and when i hooked it up and tapped the vac line, it was garbage



so i bought a new vac line and threw it on, well

my car only boosts up to 5, maybe 6 and the needle shakes like a siv and makes a rattle noise, i don't ever see it drop, and at idle, it is in the grey at 20, will boost barely to grey 10, then 0 then 5/6, wondering if this is right? could it make noise cause it is cheap? did i do something wrong?



i am also throwing p0171 or whatever lean code is

could i be in limp?



any help would be great

mosmoe (OPG)

Putting a fuel filter inline between the T and the boost guage will get rid of the rattle. I am not sure what the A4's boost to though.