Not getting any boost suddenly, waste gate?? - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


DIY Turbo Discussion greddy on a 1.8? homebrew kit?

Reply
 
 
 
LinkBack Thread Tools
Old 07-12-2014, 07:33 PM   #1
Junior Member
Thread Starter
 
Join Date: Jun 2014
Posts: 46
Total Cats: 0
Default 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.

Last edited by holymolyitsclay; 07-25-2014 at 07:23 PM.
holymolyitsclay is offline   Reply With Quote
Old 07-13-2014, 12:24 AM   #2
Junior Member
Thread Starter
 
Join Date: Jun 2014
Posts: 46
Total Cats: 0
Default

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?
holymolyitsclay is offline   Reply With Quote
Old 07-13-2014, 02:25 PM   #3
Boosting since 1984
iTrader: (1)
 
stefanst's Avatar
 
Join Date: Sep 2011
Location: Levittown
Posts: 1,198
Total Cats: 68
Default

So you were messing with the charge piping and believe that somehow messed up your wastegate? Think!
stefanst is offline   Reply With Quote
Old 07-13-2014, 03:25 PM   #4
Junior Member
Thread Starter
 
Join Date: Jun 2014
Posts: 46
Total Cats: 0
Default

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.

Last edited by sixshooter; 07-13-2014 at 03:48 PM.
holymolyitsclay is offline   Reply With Quote
Old 07-13-2014, 04:24 PM   #5
Elite Member
iTrader: (3)
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,010
Total Cats: 583
Default

Stefan's trying to tell you that it is most likely a boost leak. Check ALL of your coupler's, IC, clamps, etc.
hornetball is offline   Reply With Quote
Old 07-14-2014, 12:41 AM   #6
Junior Member
Thread Starter
 
Join Date: Jun 2014
Posts: 46
Total Cats: 0
Default

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.
holymolyitsclay is offline   Reply With Quote
Old 07-14-2014, 04:34 AM   #7
Junior Member
 
Join Date: Aug 2006
Location: Cedar City, UT
Posts: 228
Total Cats: 4
Default

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.
Dlaitini is offline   Reply With Quote
Old 07-14-2014, 02:23 PM   #8
Junior Member
Thread Starter
 
Join Date: Jun 2014
Posts: 46
Total Cats: 0
Default

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.
holymolyitsclay is offline   Reply With Quote
Old 07-14-2014, 02:25 PM   #9
Elite Member
iTrader: (3)
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,010
Total Cats: 583
Default

Does the compressor/turbine wheel spin freely?
hornetball is offline   Reply With Quote
Old 07-14-2014, 02:27 PM   #10
Junior Member
Thread Starter
 
Join Date: Jun 2014
Posts: 46
Total Cats: 0
Default

Yes. Took the intake off and the turbine is spinning fine. Minimal shaftplay and no rubbing marks on the housing.
holymolyitsclay is offline   Reply With Quote
Old 07-14-2014, 02:37 PM   #11
Junior Member
Thread Starter
 
Join Date: Jun 2014
Posts: 46
Total Cats: 0
Default

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.
holymolyitsclay is offline   Reply With Quote
Old 07-14-2014, 03:33 PM   #12
Elite Member
iTrader: (17)
 
Join Date: Aug 2007
Location: Fort Myers, FL
Posts: 2,791
Total Cats: 130
Default

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.
pdexta is offline   Reply With Quote
Old 07-14-2014, 03:37 PM   #13
Junior Member
Thread Starter
 
Join Date: Jun 2014
Posts: 46
Total Cats: 0
Default

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?
holymolyitsclay is offline   Reply With Quote
Old 07-14-2014, 03:50 PM   #14
Elite Member
iTrader: (3)
 
concealer404's Avatar
 
Join Date: Aug 2011
Posts: 8,465
Total Cats: 783
Default

Quote:
Originally Posted by holymolyitsclay View Post
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.
concealer404 is offline   Reply With Quote
Old 07-14-2014, 03:57 PM   #15
Junior Member
Thread Starter
 
Join Date: Jun 2014
Posts: 46
Total Cats: 0
Default

No, it does not leak at idle.
holymolyitsclay is offline   Reply With Quote
Old 07-14-2014, 04:00 PM   #16
Elite Member
iTrader: (3)
 
concealer404's Avatar
 
Join Date: Aug 2011
Posts: 8,465
Total Cats: 783
Default

Quote:
Originally Posted by holymolyitsclay View Post
No, it does not leak at idle.
Make a boost leak tester for $10 at Home Depot. Test for leaks.
concealer404 is offline   Reply With Quote
Old 07-14-2014, 04:10 PM   #17
Junior Member
Thread Starter
 
Join Date: Jun 2014
Posts: 46
Total Cats: 0
Default

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
holymolyitsclay is offline   Reply With Quote
Old 07-14-2014, 04:19 PM   #18
Senior Member
iTrader: (5)
 
Join Date: Nov 2013
Location: Wisconsin
Posts: 659
Total Cats: 66
Default

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.
mlev is offline   Reply With Quote
Old 07-14-2014, 04:25 PM   #19
Junior Member
Thread Starter
 
Join Date: Jun 2014
Posts: 46
Total Cats: 0
Default

I disconnected the arm, and idled the car. WGA did not move. Gave it some gas (3k rpm), did not move.
holymolyitsclay is offline   Reply With Quote
Old 07-14-2014, 04:26 PM   #20
Senior Member
iTrader: (5)
 
Join Date: Nov 2013
Location: Wisconsin
Posts: 659
Total Cats: 66
Default

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).

Attached Thumbnails
Not getting any boost suddenly, waste gate??-untitled.png  
mlev is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Project Gemini - Turbo Civic on the Cheap Full_Tilt_Boogie Build Threads 59 Yesterday 09:00 PM
LucaCarMods's Boosted Dutch Miata Build! LucaCarMods Build Threads 11 02-14-2016 07:13 AM
Going back to stock. Need some 1.6 parts. Trent WTB 2 10-01-2015 01:15 PM
Bad head gasket or ? shooterschmidty Engine Performance 8 09-30-2015 11:28 PM
Got bad Crank Angle Sensor and Random Misfire codes, but runs fine. Greasyman General Miata Chat 2 09-28-2015 11:44 AM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 07:29 AM.