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Okay, I've read numerous threads on this sound that "something" makes under approx. 2-4psi consistently.

Before, I thought it was heatshields, or possibly the chimney, because I had to do a little customizing to it due to the aftermarket DP. But, I have since ruled those issues out.

It is now very pronounced now that it has been colder outside, and there is no way it's a heatshield.
I haven't 100% ruled out a BPV problem, but I can hear the valve recirc. so I know that is not causing this sound.

I'm going to get an MBC, but I want to figure out what my problem may be before doing so. My first test is going to be the boost control solenoid.

Now, my question is, without using an MBC, and this is temporary, just to see if the ticking will reside, if I run wastegate pressure, would overriding the BCS by connecting the wastegate hose to the compressor outlet hose be a proper way to go about this?
I'm not getting a CEL, but my car is stumbling at around 5-6psi along with the ticking noise. It will climb with no problem, but it stumbles just as quickly as it gets there.

Also, the PO had replaced all Vac. hoses. I'm going to have to check to see whether or not he replaced the hose with the valve in it. That could be another issue for this.
Which vac hose has that breather valve in it?

manifold gasket leak

My vote is wastegate flutter. The sound is the wastegate clicking against the turbo housing as it opens and closes repeatedly. My car did the same thing.

jefferson wrote:My vote is wastegate flutter. The sound is the wastegate clicking against the turbo housing as it opens and closes repeatedly. My car did the same thing.

Bump
if you run just wastegate or install the MBC the noise should go away.

Boost solenoid.

Just red this on a dutch forum, guy claims to have a ticking noise.

Suggestions were:
Gasket uppipe/manifold,
A leaking IC hose,

Problem was:
A crack in his manifold

Good luck,

I have a clicking in my 1994 touring wagon. It seems to fade away around 3500-4000rpm. If it were an exhaust leak then it would be constant, so if this were the boost solenoid/wastegate flutter, would the noise go away at higher rpms.

turbodrabbit' wrote:I have a clicking in my 1994 touring wagon. It seems to fade away around 3500-4000rpm. If it were an exhaust leak then it would be constant, so if this were the boost solenoid/wastegate flutter, would the noise go away at higher rpms.

I would bet it is the boost solenoid. The previous replies were correct, that was my problem.
I rectified the issue by disconnecting the vac tubes to the solenoid and using an MBC, T'ing it off to the wastegate and turbo outlet nipple. Started off just running WG pressure to see if the clicking had subsided, and it did. So I brought it up to factory boost, and the car has worked great ever since.

I went to a local subaru shop and they had a used manual boost controller and he said he didn't recommend them. I asked why and he said they were inaccurate and would be bad for longevity. Our cars didn't even come with a boost gauge, so how did you know yours was at stock boost? If you do have a gauge, what did you use?

turbodrabbit' wrote:I went to a local subaru shop and they had a used manual boost controller and he said he didn't recommend them. I asked why and he said they were inaccurate and would be bad for longevity. Our cars didn't even come with a boost gauge, so how did you know yours was at stock boost? If you do have a gauge, what did you use?

It's very easy to hook in an aftermarket boost gauge to monitor boost levels

Forgot to add that I did this using my boost gauge, an Autometer phantom 30-0-30 one.
I certainly wouldn't plumb an MBC in without a gauge first. If you are only going factory settings, this wouldn't cause premature failure.

When it is misused is when you have a problem.