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inconsistent boost...leaks?

7K views 7 replies 4 participants last post by  RcrsWetDream 
#1 ·
ok, try to be patient with me as this is my first wrx. i was a dsm guy for a few years and finally made the switch. That said, this is a whole new beast and i almost feel lost! i have a 2003 2.0 wrx. the car has a 3 inch cat back system and was tuned by the previous owner with the cobb stage 1 accessport and a turbo xs bov. Aside from that the car is stock. when i picked the car up (bought it from a friend) i noticed it was runnin a little rough, so i changed the plugs, had the injectors cleaned, changed oil and rear end fluid...the basic stuff. im noticing very inconsistent boost and vacuum levels on my guage, granted it is the stock column mounted boost guage but my fluctuations are noticable in the performance of the car. most days the car boosts to what would be the equivalent of 14 psi and vaccum holds steady around 12 however sometimes ill see a drop in power and notice my boost wont go above about 9-10psi even at WOT, vacuum isnt as stong at this point either. i have no issues with a rough idle or anything like that. also i hear an additional sound after the bov dumps, sounds like a high pitched whistle almost and only happens when my boost is below the norm. i dusted off my boost leak tester and have pressurized the car three times, no leaks. im not familiar with boost control solenoids and restrictor pills as all my dsms were simple setups (upgraded turbo, mbc, stuff like that) sorry its so long guys but i wanted to make sure you know what ive already tried and wanted to include my mods. i did check out the forums and couldnt find an exact answer, just looking for some direction. thanks guys!
 
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#3 ·
Like John said switch out that BOV and put the stock one back on it, another thing to look over is ALL the vacuum lines make sure they are not cracked or looking old, also with the car running get a can of brake clean and spray down around the vacuum lines the bov and TB clamps and intercooler piping and listen to the car and see if you can hear a difference when you spray those spots down with brake clean. Let us know what you end up with.

Also, do you have a way to data log the car?
 
#4 ·
I won’ have a chance until this weekend to wrench on it again. Ill swap out the BOV and replace it with stock. I don’t have any way to datalog the car. As far as the brake parts cleaner, what exactly am I looking for? Thanks for the input, not too many sources of information on these cars around my town and the dealers are not tuner friendly at all. Much appreciated!
 
#5 ·
when you are spraying the brake clean around those clamps and hoses listen to the car to change sound, if it changes sound in that spot you sprayed that means you found a leak or some sort. I found a leak around my BOV and it was a little little hole in the gasket.
 
#7 ·
well, no luck finding the leak with the brake clean or swapping the bov. my car got hit by a motorhome on the 31st so ill have it in the shop to do an all over paintjob and some bolt on goodies starting in about a week or two. when i tear down to do the up pipe ill check out the rest of the lines i had trouble seeing while the car was assembled. ill post an update with the findings. on an unrelated note, should i expect any gains in power or acceleration with the catless uppipe install and elimination of the egt? im assuming ill see the turbo start to spool a bit sooner but is power noticably better?
 
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