I'm driving a '97 Audi a4 Quattro 1.8t 5 speed Aeb engine code.
anyways I just installed a boost guage and I'm seeing my vacuum is at -10inhg and I didn't know it should be around -20 until recently. my little hose that comes from the intake manifold to.... ( the DV? ) was always quite a bit junk so I figured I would start there, I got some replacement hose and reran it but still am at -10. when I run hose just from the intake to the T fitting and then close off the other end of the T fitting to the boost gauge it shows -21. but once I had it connected to the (DV?) it would go back down to around 10. could a faulty (DV?) be the issue here? also just for more information to go off of.. maybe it is relevant maybe it isn't. when I had the gauge installed the first time I was seeing that if I was in 5th going around 55 and floored I'd the boost would slowly go up to about 15 psi and then it would kind of surge? the needle would just go back and forth between around 14-16 psi. also in second my boost peaks at around 17ish psi. I do have a ko4 but no other performance mods have been done while I have owned the car. thanks much for your help