Possible boost leak problems?

[SPL_Jetta]

I recently had my car brought into Eurotech Perforance Group to fix some CEL light problems. It was running strong, but horrible surging and detonation problems.

They replaced my N249 valve, my N75j valve, and my spark plugs, and while they were at it they upgraded to X+ v .14

I got it back and now it runs smooth just at idle is slightly rough and it pulls alright but not as strong as before i brought the car into EPG. Im guessing that its a boost leak because its not throwing any codes, but i dont know where to start when checking for boost leaks, anybody have any clue also why it would be now having boost leak problems after i upgraded the chip, because before it was running stronger now, just sparraticly. Im not taking it back to EPG because they are way too busy and i think they are more concerned about getting the cars outa there. Im going to take it to Autofab on monday, hopefully they can figure out whats wrong with it. Anyone else know whats wrong with it?

Thanks

[benwaballs]

hook a smoke machine up to it. quick and easy

[SPL_Jetta]

quick, yes, however i dont have a smoke machine, so not easy

[Decker1.8t]

this is GIAC ver. 14 + N75j might = too much smoothing which would in turn make your car feel slower. try either a stock or and H valve.

if you decide to go w/ the H valve, watch out for limp mode.

[4dmin]

well i will tell you this is the exacty reason why you dyno your car as often as you can or atleast for each setup so you know where you stand. its really the only way to tell whats up w/ the power. also watch your boost gauge ;)

v14 is very smooth but strong, but a boost leak will defiantely act up

[SPL_Jetta]

Well i got an update, its running strong whenever i disconnect the battery, but its surging like all hell and its sparratic boost. It works sparraticly, and is constantly switching between normal mode and limp mode. This car is getting annoying.

Also when the boost was working, i was going about 45 mph in 5th gear, i pressed on the gas decently hard and some poping noises came from underneath my hood, and they were loud, loud enough to be heard over my music, and i could feel it in the floorboard and steering wheel.

Any clues as to what is going on.

[4dmin]

well the flash does take a few turn keys to take full effect on the ecu, i know when i run in race mode it runs better after driving on it for a couple days.

surging is normal on most chips, shouldn't be that bad though, you probably need to check all of your lines... :goodjob:

[SPL_Jetta]

im starting to think it might be the N75 valve, because whenever it goes into limp mode it runs very smooth, no hesitation or anything. However when its not in limp mode it runs very rough, and its very choppy, surging like all hell. I need to get ahold of a stock N75 to test my theory