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.

---

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

I know, that's what I meant. The "lever" is the thing that I was testing to see if it moved. (The thing I was playing with in the video I linked to)

Have you considered making a $10 boost leak tester from Home Depot?

This link is not public (notice the https instead of http).

Link is public. Just secure site instead of normal HTTP.

Not sure why the board didn't like it, though. I use https links all the time.

Hmm not sure why you guys can't see the video.

No I have not made a boost leak tester. I plan on borrowing a friend's here soon.

I saw the video. Didn't see anything immediately alarming, but then again my experience with internal wastegates is usually as follows: Weld shut, utilize external gate.

That wastegate movement looks OK. Looks a bit constrained on the opening angle, but that would cause boost creep, not low boost.

I don't like the amount of up/down (axial) movement that lever can perform. If it's not aligned properly, there's no way the WG can actually close.
I'd say remove downpipe and take a look-see.

Hmmm . . . . Hadn't noticed that. It definitely looks abnormal.

You didn't say if there was oil in your intercooler piping.

If there was, then when you took the silicone couplers off you may have gotten oil on the sealing flange of the coupler or the intercooler. If so, that will lubricate it, and it will pop off again under pressure, even with the hose clamp tight. It happened to me once, and I had to take it all apart and clean everything with rubbing alcohol to get it to seal properly.

You won't get the wastegate to move revving it at idle. If you have a compressor and a regulator, you can test it with air pressure directly.

--Ian

I chased a problem like this two years ago and found that a whole lot of rust had broken loose from inside the downpipe and clogged the cat. Had spent days looking for a boost leak, pulled apart everything twice to no avail.

Finally broke the cat intake side loose, put two nuts as spacers to hold it open with longer bolts, and took it for a ride getting full boost.

Took the cat off and dumped out the rust, then I ordered a turbo-back system from Artech.

Above post for information, but I just looked at your video.

Seems to me that there is not sufficient movement. There have been many instances of the wastegate being held by the downpipe flange interfering with the wastegate flapper and holding it open.

Loosen the bolts on the downpipe flange and move it slightly to see if the wastegate will move freely. Get it to a point that it moves freely and re-tighten the bolts.

My boost problem I had was a clogged cat. Check out my thread 'only getting 2psi' and look at the last page. I had bought the car as is and finally got it back on the road to find out it wouldn't boost past 2psi. The wonderful guys here helped me diagnose it.

The movement on the wastegate looks weird enough to me that I'd pull the downpipe off and see what's really going on in there. I don't think they're supposed to move up and down like that and the open/closed movement looks pretty restricted to me.

Sounds like the cat could be a likely cause. I will definitely disconnect it and see what happens. Also, I will be sure to remove that downpipe to see if my waste gate movement gets less restrictive.

Thanks for the responses so far, I will get back to you all with findings.

In the meantime, any other suggestions are welcome.

From a troubleshooting standpoint, the turbo is just a compressor driven by a turbine, powered by exhaust.

If the exhaust is flowing (check the cat, as a clogged cat can cause lack of spool), and the turbine is getting flow and spinning(pull the hotside apart, check the wastegate arm, check that the turbine spins freely), and the compressor is able to build boost (check for boost leaks, and that the compressor spins freely), you will build boost. Unless the front falls off.

Check those things. I doubt anyone has any other suggestions until then.

Looking at that video, there is no way the arm should have lifted vertically like that with the shaft coming up out of the hole like that. Your wg is fucked up. Either the flapper had fallen off or it is misaligned from the hole it is supposed to cover.

Keith

Oh wow, I didn't watch the video (now I have) but twodoor is right. Your wastegate should not be able to move up and down (vertical) like that. Pull the downpipe off and check that bitch out.

Take one of these:

https://www.miataturbo.net/attachmen...ine=1405527965

Screw it into one of these:

https://www.miataturbo.net/attachmen...ine=1405527965

Clamp it on your turbo intake side and pressurize your intercooler tubing with it.

Listen for leaks and spray a solution of water/soap on suspect areas to verify. The soap will bubble if air is coming out

The more I researched clogged cat symptoms, the more I thought it was definitely the issue. Unfortunately the cat is welded to the rest of the exhaust, so I disconnected the O2 sensor and the downpipe from the turbo and went for a drive. No difference really. The car seems to pull a bit harder but still no boost. In fact, the vacuum got to a max of about -10 or -8 vacuum where as before it was almost at -3. Not sure what's up with that.

On the drive my waste gate arm c clamp fell off, there for taking the arm off the wastegate flapper, so I assumed that's what my problem was. Nope, bought another c clamp and still having problems.

I will make a boost leak tester and do that. Also, I will check out the waste gate.

Again, thanks for all your help thus far.

Think I found my issue. Let me know what you guys think and how you suggest going about fixing it

Wastegate issue:

That wastegate should not move up and down like it does. You will probably need to source a new housing.

Was this supposed to be http://youtube/vbbT4U5_gb8 ? I can't check from work, so don't know if I fixed it :)

Keith

Edited.

I embedded the video correctly in the first post that you had it.

Thanks. I'm posting from my phone so the 'video' option isn't available like it is on the full site.

There's only one proper MT.net answer on what to do now: Weld WG shut and run ALLOFIT!

Been calling around and no one sells just the wastegate flapper housing (not sure of the technical name of it.) It's an eBay turbo anyways (godspeed) so i don't even think it's worth the money and effort to fix it. Looks like a new turbo is in my future.

Or weld it up and go to an external wastegate.

Wouldn't I need a new manifold if I went that route?

Or have a hole drilled and a flange welded onto your prexisting one.

Disclaimer: This comment is being made without looking at the picture to see if there is room. :dealwithit:

Ended up just ordering a new turbo. The company from which I bought the turbo had awful customer service, and they wouldn't let me purchase just the wastage flapper housing.

Should make a nice center piece for the living room table.

Dude are you kidding me? You can get new and used turbine housings all over the net. If you would have posted a wtb i doubt you would paid more than $50 for a used turbine housing

Well I got it from a friend's shop for $100 with the discount he gave me, so it just wasn't worth it for me to try to get a new housing etc.