Ok I have a 99.5 a4 1.8 so I just put a biost gauge on it and seen I have a problem as mu car.starts to boost right around 2k or so I hit 8 psi as I run thru the rpm my boost pressure starts To fall at 6 grand I only have 2 psi but I dont think its a leak cause I can put it in 5th gear at.like 30mph hold it to the floor and hold 8 pounds for a very long time till I get to about 4500 then it start to drop plz help

 

it's hard to believe that nobody replied to your problem bro

so here is whats going on....

all the audi/vw stock do that... the boost climbs up to its peak then the electronic boost control in the ecm slowly brings it down as the rpm's climb tell it crashes back down to barely boosting.

this guy here is running a little bit more power but the same would apply to you just lower psi/ bar
VWVortex.com - How to make K04 boost curve more flat. Any ideas ?

don't worry its not a huge deal my TT does the same thing, but if your looking for more power i would recommend upgrading your turbo or installing a mbc(manual boost controller). but if your turbo is on its last lag it wont hold boost very long with a mbc. installing it on my car is what made me realize that my k03 was shot.

 

Best plan is to get the ECU upgraded so the tuning parameters are all in place for higher boost rather than slapping an MBC on and having the fuel and timing trimmed only after the ECU sees sensor feedback and adjusts. Upgrading the turbo is a long list of mods away from stock - no need unless you're going with a full turbo-back exhaust, intercooler, injectors, and a tune appropriate to these parts.