Hey everyone, I was checking for vacuum leaks today and I noticed something strange. It seems my stock wastegate leaks out a bit when subjected to positive pressure. The strange thing is it holds a vacuum perfectly, which makes me wonder if it is designed to do this for some reason. Any thoughts?
Wastegate actuator leak?
- Thread starter peepsalot
- Start date
Pressure
You know guys, I could be in left field here, this kinda reminds me of a trick question on a college exam. You are 100% sure of the answer but then another option is thrown out there and makes you second guess yourself!
I believe it is supposed to. The reason why is because if it didn't the diaphram would pop like a balloon. Basically, as the diaphram moves forward to move the arm, the opposite side pushes air out a breather hole. But then again, I may be tricked up. Hope this helps.
Since we are on the topic, I have never tested for leaks, how are you doing this? Are you disconnecting the pipe off the TB and plugging it? Where else did you find a leak?
peepsalot said:
You know guys, I could be in left field here, this kinda reminds me of a trick question on a college exam. You are 100% sure of the answer but then another option is thrown out there and makes you second guess yourself!
I believe it is supposed to. The reason why is because if it didn't the diaphram would pop like a balloon. Basically, as the diaphram moves forward to move the arm, the opposite side pushes air out a breather hole. But then again, I may be tricked up. Hope this helps.
Since we are on the topic, I have never tested for leaks, how are you doing this? Are you disconnecting the pipe off the TB and plugging it? Where else did you find a leak?
Well, I am only testing my vacuum hoses for now. I have a handheld vacuum pump(one of those multi purpose brake bleeding type deals) that I can attach to each line, and see if it is leaking. Actually, my vacuum pump failed and wouldn't hold a vacuum, so I was using my mouth(ewwww), and that is how I found that my wastegate leaks under pressure. I got a new vacuum pump now though. 
I found a small leak from my new greddy type S BOV, that was cured by putting teflon tape on 1) the spring adjustment screw, and 2) the vacuum signal nipple.
I haven't tested the pipes yet like you mentioned, but that is my next plan. I was planning on disconnecting the filter on my SRI, and disconnecting the pipe from the TB. Then plug both ends and pressurize it somehow. Gotta take it one step at a time though.
I found a small leak from my new greddy type S BOV, that was cured by putting teflon tape on 1) the spring adjustment screw, and 2) the vacuum signal nipple.
I haven't tested the pipes yet like you mentioned, but that is my next plan. I was planning on disconnecting the filter on my SRI, and disconnecting the pipe from the TB. Then plug both ends and pressurize it somehow. Gotta take it one step at a time though.
If anyone would be so kind, you could test your own wastegate line by pressurizing it with your mouth, to tell if it is normal. I was able to keep pushing air through mine.
If you have stock vacuum hoses still, you probably wanna have some replacements ready, cause they could break while trying to remove them.
If you have stock vacuum hoses still, you probably wanna have some replacements ready, cause they could break while trying to remove them.
The things I do...
The things I do for this forum... Unfucking believable! LOL!!! Before this, the worst thing I had done to the car was cut my hard pipes and move the MAF to the pressure side only to lean out for two weeks and knock probably 30,000 miles off the life of the vehicle! LMAO!
OK, I took the wastegate actuator line off my MBC and blew into the wastegate. I blew as hard as my 3 pk a day lungs could blow and to no avail. Not a single hiss or leak. Unless your lungs are powerful enough to blow 5~6 psi, you should not leak.
I sincerely hope it is not your actuator and if it is I hope your warrenty will cover even though Mazda (might and I do mean might) suspect you are using a boost controller seeing how you 1) knew exactly what was wrong with the wastegate and 2) have the sensor line unglued right where a tuner may stick a boost control selenoid. Check around the actuator nipple just to be sure.
By the way, I am on an AF installation, on my lunch break, outside of my school building, under my hood, with my mouth on a rubber tube.... I better get a positive rep for this!!!! (rofl2)
peepsalot said:
The things I do for this forum... Unfucking believable! LOL!!! Before this, the worst thing I had done to the car was cut my hard pipes and move the MAF to the pressure side only to lean out for two weeks and knock probably 30,000 miles off the life of the vehicle! LMAO!
OK, I took the wastegate actuator line off my MBC and blew into the wastegate. I blew as hard as my 3 pk a day lungs could blow and to no avail. Not a single hiss or leak. Unless your lungs are powerful enough to blow 5~6 psi, you should not leak.
I sincerely hope it is not your actuator and if it is I hope your warrenty will cover even though Mazda (might and I do mean might) suspect you are using a boost controller seeing how you 1) knew exactly what was wrong with the wastegate and 2) have the sensor line unglued right where a tuner may stick a boost control selenoid. Check around the actuator nipple just to be sure.
By the way, I am on an AF installation, on my lunch break, outside of my school building, under my hood, with my mouth on a rubber tube.... I better get a positive rep for this!!!! (rofl2)
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OK, well, I guess my actuator is screwed. Kinda sucks cause I don't even know where to get a replacement.
I know mazda ain't gonna warranty it, I've actually removed my turbo and drilled a hole in the compressor housing, haha don't ask. That has nothing to do with the wastegate anyways, but they will see that(among other things) and freak, so yeah, no warranty work for me.
I don't know if it really makes much of a difference though. I mean, it doesn't leak from a vacuum, so it shouldn't be affecting my idle, and it only leaks a little bit on boost.
I didn't hear it hissing by the way, I could just tell that I was slowly able to put more and more air into it, not a huge leak.
I know mazda ain't gonna warranty it, I've actually removed my turbo and drilled a hole in the compressor housing, haha don't ask. That has nothing to do with the wastegate anyways, but they will see that(among other things) and freak, so yeah, no warranty work for me.
I don't know if it really makes much of a difference though. I mean, it doesn't leak from a vacuum, so it shouldn't be affecting my idle, and it only leaks a little bit on boost.
I didn't hear it hissing by the way, I could just tell that I was slowly able to put more and more air into it, not a huge leak.
Do you get any boost spikes? I think mine is ****** up i'll try blowing in it, give me a second.
EDIT: I just blew into mine and i could hear the rubber flap open, and then suck it closed. Then i could just blow air thru it. I think mines faulty also.
EDIT: I just blew into mine and i could hear the rubber flap open, and then suck it closed. Then i could just blow air thru it. I think mines faulty also.
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I think mine is as well, I have the same spiking problem that your all talking about, I'm going outside to go blow on mine and see what happens....... Weird I tell you Weird! Ok, brb:
Well, I can blow through mine as well. I think I'm going to test it out tomorrow and go buy some bulk silicone hose. I'll try that and see if I can blow through that hoping tht maybe the stock hoses have cracked. I mean I can blow through it and you can tell it's leaking but nothing major but you can still tell it's leaking. If that doesn't work then I'll get a new actuator put on, unless there not that expensive in which case I would rather do it myself.
Well, I can blow through mine as well. I think I'm going to test it out tomorrow and go buy some bulk silicone hose. I'll try that and see if I can blow through that hoping tht maybe the stock hoses have cracked. I mean I can blow through it and you can tell it's leaking but nothing major but you can still tell it's leaking. If that doesn't work then I'll get a new actuator put on, unless there not that expensive in which case I would rather do it myself.
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I don't really have much problems with boost spikes or overboosting (shrug)
I still think it could be that they are designed to let out a small amount of air for whatever reason.
But keep me updated on how your cars are doing guys. Oh I have replaced the hose with silicone, and I tested the hose by itself for leaks, so mine is definitely in the actuator.
I still think it could be that they are designed to let out a small amount of air for whatever reason.
But keep me updated on how your cars are doing guys. Oh I have replaced the hose with silicone, and I tested the hose by itself for leaks, so mine is definitely in the actuator.
My actuator was ******. There was a hole in it. It would whistle really loudly under vac and it would go away under boost and i would only boost like 4psi.
Mazda Warrantied my turbo.
*edit* i think its normal but don't quote me on it. *edit*
Mazda Warrantied my turbo.
*edit* i think its normal but don't quote me on it. *edit*
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DSMConvert
AWD...say Bye Bye
- :
- Titanium MS6
yea actuator shouldnt leak....leaking under pressure on a car engine that lives off of vac is a very bad thing.....had the same problem on mine and had it replaced under warranty...grea tthing is it can only be ordered with the turbo so i got a whole new turbo out of the deal too! Signs of this will include irradic idling, whistling, crappy running.....
I had a problem with my actuator as well. My boost would not stay the same for any two runs, however it never spiked. I got myself a beefier actuator designed for a T3 turbo. I had to modify the stock bracket just a tiny bit and make the rod a little longer because as is when attached to the turbo the spring would be very tight and I'd boost who know how much(over 15psi easy) Otherwise it fits well and works a lot better than stock actuator. The new one will not open until the set boost unlike the stock one which starts opening partially before full boost and leaks boost.
NJMSP42385
Member
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- Mazdaspeed Protege 2003.5
Seems I might have the same problem, subscribing to find out the results of the install
