hey guys just got my first subie
 

Have had my wagon for about a month know and ever aince i bought it ive noticed the boost oscilation issue have neen trying to track it down for.a.xouple weels and before i go buy a new bcs i was seeing if i could meet up with someone and try theres i hate throwing money at things for no reason ha. thanks or id anyone could maybe help diagnose the problem thay would be great ill bring the beer ha ha

Welcome.

I would suggest you read this
We are far more likely to help if you use capital letters, paragraphs, punctuation, etc...

Sounds like it probably a post MAF air leak, vacuum leak and/or a bad tune than a bad bcs.

What tune and/or other mods are on it? CAI?

Car prob has a tune on it or a aftermarket BCS. From what your describing it's overboosting and then compensating.

Cory

Dean sorry about that i was typing that kind of angry cause i can't figure this oscilation out on my car and writing from my crappy droid doesn't help. Would you happen to have a leak tester of some sort or maybe help me try and track this problem down?
Renosubby im the one who posted on your fb wall yesterday for your email i think. Im going to send you an email today about everything that's goin on. But i know it has the stock bcs on it and everything else is stock besides the cat back i put on and a drop in k&n but it did it before i did those things..i know its deff over boosting though cause my boost gauge will show about 16 peak than oscilate between 10-15 psi

No tune at all? How do you know it doesn't have a flash from previous owner?

Does it hunt at idle? (AC off)

If you have it, put back in a paper filter and clean the MAF sensor. Check and be careful of the MAF o-ring when you do.

Check all the vacuum hoses. Replace anything crispy especially near turbo.
Correct/any pill in the BCS/wastegate T line?

Air leak is easy. Check the hoses for visible cracks, cuts, crispiness loose clamps. Spray carb cleaner around the intake hoses including intercooler Y pipe. All clamps clicked on air box? Plastic turbo inlet giant corrugated thing is common failure point.

Borrow a cable and log it. Boost gauges lie.

Well i mean as far as my knowledge from the 1st owner it was completely stock.
Not hunting at all it idles smooth.
Ill get some maf cleaner today and try that.
As far as the vacume hoses when i went and got my smog done i was pokin around checking hoses and one of the lines coming from the t broke so a week ago i went and bought the 3 lines that go to the turbo and bcs including the t and a new restrictor pill. Ive searched and searched all the other hoses look and feel fine.
As far as logging my buddy just gave me his cable from his wrx he sold awhile back. How do i go about doing this do i download a program first? I dont wanna screw anything up. Thanks

You sure the T was installed correctly? If you get it backwards, you get weird boost issues. Keep in mind, even if you re-installed them the way the old ones came out, it may have been backwards in the 1st place.

Check the FSM: http://www.seccs.org/tech/2002%20WRX/index.html

There is a specific way for the t? I never read that on the forums when finding out about the lines and restrictor pill but. Can you explain how the t goes cause right now i have it hooked up to were the longer of the 3 points is going toward the bcs

I don't remember specifically, and I don't have access to a WRX right now. But if the pill is on the wrong site of the T, it can't restrict the wastegate input properly, and the car will boost oddly.

This might help:

http://www.perth-wrx.com/vb/mechanic...-you-need.html

Looks like the pill needs to be in the hose attached to the compressor outlet on the turbo.

Ha thats the forums i found on google when installing it i actually bought the hoses first before i realized tou had to have the pill so before i put the pill in a couple days later when subaru got it in i was getting the usual 7 psi max but no oscilatimg at all went right up to 7 and held there. Than when i installed the pill it went back to the crazyness.

Could be the wrong pill. There were a number of them, and you can't trust a dealer to get the right one. Matt at KSPEED will have all of them.

At some point you might want to take it to KSpeed and let them figure it out.

Were are they located at ive never heard of them before.