Not getting any boost suddenly, waste gate??
 

I took the turbo outlet coupler off the turbo, put it back on. Suddenly, boost was bad. Took my coupler back off to see what was going on, and it is absolutely destroyed, so I thought "ok, coupler is just bad, time to replace it." So I replaced it with a new tube, and I am STILL having the same problem.

I have no idea what's going on. Boost was great until I removed that coupler. Gradually it has gotten worse and worse, and now I have no boost at all, and the car runs like absolute garbage at about 4.5k rpm, there's a huge delay at 5k, and then it goes to redline, but it seems like it's very very hard on the car to get to redline. Vacuum stays at -4 or -3, and never gets into the boost range.

Any help appreciated. Thanks.

Update: Took off the wastegate completely and left the arm in the "open" position, went for a drive. No difference at all to when it is closed. Does this rule out wastegate?

So you were messing with the charge piping and believe that somehow messed up your wastegate? Think!

The charge pipe was stuck. I took a flathead and tried prying it off. Screwdriver slipped. Hit something. Couldn't tell what. Car doesn't boost. Saw a nick in the wastegate hose. Wondering if this could cause no boost, and if so, what it could be otherwise.

Stefan's trying to tell you that it is most likely a boost leak. Check ALL of your coupler's, IC, clamps, etc.

Bringing the car in to a performance shop tomorrow so they can perform a series of tests. I can't find the boost leak myself (if that's even it) and don't really know where else to go from here.

Do not waste your money, open the hood and crawl under the car and go slowly from the turbo to the throttle body checking every single connection.

Then once you do that check them again

You said you took one off.. did you not looses up another to take it off?

You need to make sure that every single clamp is tightened.. and if you are sure you tightened them down.. check them again just because.

I just undid pretty much every clamp, coupler and tubing from my turbo to the throttle body, inspected the tubing, inside the tubing, and reinstalled them carefully and tightened the clamps. Went for a drive, same as before. This is driving me crazy! The car drives fine before 4.5k rpm, and then it just craps out. Boost never goes beyond -3 vac. Frustrating.

The couple times I've "gotten on it" since this whole ordeal, I can hear an incredibly faint BOV noise right around -3 vac when I let off the throttle. I don't know if that means it would be leaking before or after the BOV, or if it's even leaking at all.

Does the compressor/turbine wheel spin freely?

Yes. Took the intake off and the turbine is spinning fine. Minimal shaftplay and no rubbing marks on the housing.

Here's a bit more info. Not sure how significant this is, but the first time driving the car after taking the coupler off, I still had boost, but noticed it was boosting slower and the car felt like it had less power. I remember thinking "Hmm, seems a bit slower, must just be my imagination". Drove it for a couple more days until the car started making a pretty significant "rattling" noise right around boost, and the car was down on power a significant amount at that time. I was about an hour from home when I realized this, so I drove home staying out of boost. When I got home, I noticed the turbo to manifold bolts were a little loose and causing a small exhaust leak. Gasket was broken in half between manifold and turbo. Got a new gasket, new turbo-manifold studs/bolts, tightened those up, rattling noise went away, no more exhaust leak from what I can tell. So now, there's no rattle, but still no boost.

Again, not sure if this has anything to do with anything, but thought I'd share just in case.

From what you're saying it pretty much has to be a massive boost leak. If the piping is all connected, did you check the BOV? Maybe it's venting all the time.

Is there any way it could be the wastegate flap not closing? I'm thinking that maybe when my screwdriver slipped, it hit the waste gate arm and messed it up somehow. Especially since it happened only after taking that coupler off. Kind of a stretch but I'm grasping at straws here. I've heard of this happening with some turbos.

I've looked at the BOV, but haven't thoroughly inspected it. What should I be checking for on the BOV to see if it's venting all the time?

.... Start the car, feel for a big rush of air coming out of it.

No, it does not leak at idle.

Make a boost leak tester for $10 at Home Depot. Test for leaks.

Took the arm off my wastegate to see if there was anything weird going on. Is this supposed to happen? (Only a small amount of play, the WG joint being able to ride up so much, etc)

https://www.youtube.com/watch?v=-_iAMnlObNk&feature=youtu.be

Did the front fall off?

Seriously though, sounds like a boost leak.

Also, disconnect the WGA arm, and shut the WG, and then let the car idle. when you let go of the WG, it should get pushed open even from idle exhaust gasses. Push it closed again and let it go. If it opens back up again, that means it's blocking air when it's closed and is at least partly working. Unless you want to tear the hot side apart and check it.

I disconnected the arm, and idled the car. WGA did not move. Gave it some gas (3k rpm), did not move.

Sorry, to be clear I don't mean the WGA arm, I mean the little lever that's physically connected to the wastegate stopper--the one that you had to pull the C clip off of to disconnect the WGA.

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EDIT: here, if the left cirlced bit is blocking air, the air will push it open, and then the right circled bit will move (which is visible without removing the turbo).

https://www.miataturbo.net/attachmen...ine=1405366277