wierd problem at start up, tons of knock

[white 2g awd]

well, i've posted a few times, but now, i have a keydiver chip with the knock gauge, but when ever i first start it up, and try to drive, i could sit and floor it and it won't really go anywhere it will only do about 5 mph, and the knock guage shoots way up, then all the sudden it feels like a car rear ended me, and it just goes like a bat outta hell. then get to the stop sign down the street and it does it again, it usually does this about 2-3 times, then after that, its fine, it started right after i hooked up my boost and a/f guage, no other mods were done yet, still stock. and it only does it when its cold, if i drive it for an hour, let it sit for 10-15 min. its fine, but when its cold it does this. any ideas?? also, i think my isc is starting to go out, cause after some hard driving i get a pretty bad idle surge. thanks for the help.

Dustin

 

[98TsiAWD]

Check your boost guage fittings, they may be leaking. I think vaccum leaks usually get better when the rubber warms up, but Im not for sure.

As for the knock readings, that is weird being as its only for a few minutes.

 

[white 2g awd]

yea, i did check the fitting at the boost gauge, and it was loose a month or so ago, i tightened it as much as i could, any more, i'm affraid i'm going to break the plastic on the gauge, it did help a little, and at idle i'm getting right at 20psi of vac. so i don't know that its a vacuum leak either, cause i've been told thats pretty good (20psi) i also thought maybe it could be my fuel system, but i replaced fuel pump, filter, and injectors.