Not getting any boost suddenly, waste gate?? - Page 2 - 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 07-14-2014, 04:32 PM   #21
Junior Member
Thread Starter
 
Join Date: Jun 2014
Posts: 46
Total Cats: 0
Default

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)
holymolyitsclay is offline   Reply With Quote
Old 07-14-2014, 04:55 PM   #22
Elite Member
iTrader: (3)
 
concealer404's Avatar
 
Join Date: Aug 2011
Posts: 8,465
Total Cats: 783
Default

Have you considered making a $10 boost leak tester from Home Depot?
concealer404 is offline   Reply With Quote
Old 07-14-2014, 04:57 PM   #23
Elite Member
iTrader: (3)
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,010
Total Cats: 583
Default

Quote:
Originally Posted by holymolyitsclay View Post
https://www.youtube.com/watch?v=-_iAMnlObNk&feature=youtu.be
This link is not public (notice the https instead of http).
hornetball is offline   Reply With Quote
Old 07-14-2014, 05:02 PM   #24
Elite Member
iTrader: (3)
 
concealer404's Avatar
 
Join Date: Aug 2011
Posts: 8,465
Total Cats: 783
Default

Quote:
Originally Posted by hornetball View Post
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.
concealer404 is offline   Reply With Quote
Old 07-14-2014, 05:51 PM   #25
Junior Member
Thread Starter
 
Join Date: Jun 2014
Posts: 46
Total Cats: 0
Default

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.
holymolyitsclay is offline   Reply With Quote
Old 07-14-2014, 05:52 PM   #26
Elite Member
iTrader: (3)
 
concealer404's Avatar
 
Join Date: Aug 2011
Posts: 8,465
Total Cats: 783
Default

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.
concealer404 is offline   Reply With Quote
Old 07-14-2014, 05:58 PM   #27
Elite Member
iTrader: (3)
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,010
Total Cats: 583
Default

That wastegate movement looks OK. Looks a bit constrained on the opening angle, but that would cause boost creep, not low boost.
hornetball is offline   Reply With Quote
Old 07-14-2014, 06:05 PM   #28
Boosting since 1984
iTrader: (1)
 
stefanst's Avatar
 
Join Date: Sep 2011
Location: Levittown
Posts: 1,198
Total Cats: 68
Default

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.
stefanst is offline   Reply With Quote
Old 07-14-2014, 08:09 PM   #29
Elite Member
iTrader: (3)
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,010
Total Cats: 583
Default

Quote:
Originally Posted by stefanst View Post
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.
hornetball is offline   Reply With Quote
Old 07-15-2014, 03:01 AM   #30
Elite Member
 
codrus's Avatar
 
Join Date: Mar 2007
Location: Santa Clara, CA
Posts: 3,878
Total Cats: 344
Default

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
codrus is offline   Reply With Quote
Old 07-15-2014, 06:46 AM   #31
AFM Crusader
iTrader: (18)
 
olderguy's Avatar
 
Join Date: Oct 2004
Location: Wayne, NJ
Posts: 4,438
Total Cats: 84
Default

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.
olderguy is offline   Reply With Quote
Old 07-15-2014, 07:59 AM   #32
AFM Crusader
iTrader: (18)
 
olderguy's Avatar
 
Join Date: Oct 2004
Location: Wayne, NJ
Posts: 4,438
Total Cats: 84
Default

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.
olderguy is offline   Reply With Quote
Old 07-15-2014, 08:55 AM   #33
Junior Member
 
Join Date: Apr 2013
Location: Elgin, SC
Posts: 359
Total Cats: -4
Default

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.
whinin is offline   Reply With Quote
Old 07-15-2014, 10:48 AM   #34
Elite Member
iTrader: (17)
 
Join Date: Aug 2007
Location: Fort Myers, FL
Posts: 2,791
Total Cats: 130
Default

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.
pdexta is offline   Reply With Quote
Old 07-15-2014, 11:37 AM   #35
Junior Member
Thread Starter
 
Join Date: Jun 2014
Posts: 46
Total Cats: 0
Default

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.
holymolyitsclay is offline   Reply With Quote
Old 07-15-2014, 02:20 PM   #36
Senior Member
iTrader: (5)
 
Join Date: Nov 2013
Location: Wisconsin
Posts: 659
Total Cats: 66
Default

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.
mlev is offline   Reply With Quote
Old 07-16-2014, 07:12 AM   #37
Senior Member
iTrader: (2)
 
Join Date: Mar 2014
Location: Meridian, Mississippi
Posts: 637
Total Cats: 42
Default

Quote:
Originally Posted by holymolyitsclay View Post
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=-_iA...ature=youtu.be
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
Twodoor is offline   Reply With Quote
Old 07-16-2014, 08:53 AM   #38
Junior Member
 
Join Date: Apr 2013
Location: Elgin, SC
Posts: 359
Total Cats: -4
Default

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.
whinin is offline   Reply With Quote
Old 07-16-2014, 01:26 PM   #39
Junior Member
iTrader: (2)
 
Join Date: May 2011
Location: AL
Posts: 233
Total Cats: 10
Default

Take one of these:



Screw it into one of these:



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
Attached Thumbnails
Not getting any boost suddenly, waste gate??-am20906_500.jpg   Not getting any boost suddenly, waste gate??-pvc-end-cap6.jpg  
mellowout is offline   Reply With Quote
Old 07-16-2014, 02:15 PM   #40
Junior Member
Thread Starter
 
Join Date: Jun 2014
Posts: 46
Total Cats: 0
Default

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.
holymolyitsclay 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 12-15-2017 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 12:33 AM.