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-   -   Boost Leak HELP!!! (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/boost-leak-help-976345/)

Tyler [S5 FC] 11-09-11 12:44 PM

Boost Leak HELP!!!
 
So 5 days ago my car was running fine (except it doesn't idle), then the day after I start up my car and there is a boost leak, like it happened while it was sitting over night. I have a top mount ic and checked all the piping and the leak isn't there. (Also, on a side note, while driving I'm pretty sure I hear the leak on the drivers side.) The only places I see where it could be leaking are here;

http://i235.photobucket.com/albums/e...dom/leak_1.jpg
There are two of these plugs by the oil filter, one is connected to a hose and the other looks like this.

http://i235.photobucket.com/albums/e...dom/leak_2.jpg
This one is on the rotor housing next to where it says 13B. (pretty sure it's not this one)

http://i235.photobucket.com/albums/e...dom/leak_3.jpg
This is under my ic and pretty sure this has always been unplugged.

Are any of these where I'm leaking? I've checked everywhere on the uim and all the males either are blocked off or have hoses running through them. Any ideas guys? I'm at a loss and don't wanna spend $$$ to take it somewhere. I've tried spaying carb cleaner around the gaskets as well to see if the leak was there and nothin. Please help me :(

AGreen 11-09-11 03:52 PM

Are you shitting me?

1) that's the clutch slave cylinder bleeder
2) that's a non-used bolt hole on the engine
3) that's the oil pressure sender

How do you know you have a boost leak? Why won't the car idle?

Tyler [S5 FC] 11-09-11 04:08 PM

No I'm not shitting you. I'm not a mechanic, my bad, I'm trying to learn this shit as I go, hence why I'm asking questions. My car was pushing 6psi one day. The next day it's only at 2psi. I can hear the turbo spool up, and I can now hear a whistling noise and the blow off valve leaking somewhere in the engine bay (sounds like the drivers side)... Anyways, I can hear it spool up and my car is not getting any faster when it does. Which I'm assuming is a boost leak.

And I have no idea. My car hasn't idled properly since I did the turbo swap, and have had 4 friends and 3 shops try to figure it out with no luck.

And yeah, I kinda figured it wasn't any of those. Its just I can't find anywhere where it could be leaking. I was talking to an Evo guy and he said it could be my wastegate somethin or other, actuator maybe. Lol, I forgot what he said.

SpikeDerailed 11-09-11 04:18 PM

Number 3 is not the oil pressure sending unit. It wouldnt be located under the ic, it would be located under the oil filter. The more likely case is that it is the dashpot(dont have a tii to compare to).

schaft 11-09-11 04:25 PM

Pull the elbow to the throttle body and make sure there are no cracks. I know you said you did but double check it and make sure its clamped on tightly with no areaway bunching up, a gap her would cause both ur problems.

Bamato 11-09-11 04:27 PM

I'd say you have false air somewhere in the system. Most likely before and after the turbo. Check the large spots first. Are you still sporting the stock turbo inlet duct? Those usually crack, or harden up so much that there's no way for them to seal against the turbo, AFM, BAV, etc... Pull it off, check for hairline cracks around the turbo side and make sure the clamp still tightens down enough to create a good seal.

The next spot I'd check would be the intercooler and all the piping for it.

Bamato 11-09-11 04:30 PM


Originally Posted by AGreen (Post 10855918)
3) that's the oil pressure sender

I'm not so sure on this one. I believe it's just a dash-pot on the throttle body. :scratch:

Tyler [S5 FC] 11-09-11 05:32 PM

I'll check all this stuff tonight. Thanks for the help. And yes, I do need to replace the gasket after the turbo (in between turbo and dp). I bought a universal one, but didn't fit. Still trying to find the right size.

AGreen 11-09-11 07:17 PM

I couldn't really tell what pic 3 was, kinda blurry. Definitely not a source for vacuum/boost leak.

More likely problem is that the little clip fell off the wastegate actuator, allowing the wastegate to flap around inside at free will. 2 psi sounds about right. FC3S pro website says that after porting his wastegate, even with a 3" exhaust, the actuator arm came off and was only able to produce 1 psi of boost.

If you look under the turbo, you should see a rod that goes from the front of the turbo, to a small arm towards the back. If that arm is dangling loose, you've found your problem.

There are a couple ways of checking for a boost leak, but the only way you or I would be able to do it is by taking it apart and visually inspecting each component.

Have you tried idling it and putting a hand over the blowoff valve? If it's getting stuck open, it'll definitely leak under boost, and at the same time it'll have a hard time idling as well.

I just took a look at your build thread, looks like you have a knockoff blowoff valve. That was a culprit on my car as well until I got a legitimate HKS unit.

J-Rat 11-09-11 08:20 PM

That was funny... Vac leak from the slave cylinder.

flexxi 11-09-11 10:47 PM


Originally Posted by J-Rat (Post 10856244)
That was funny... Vac leak from the slave cylinder.

^ lol

87 t-66 11-10-11 08:10 AM


Originally Posted by AGreen (Post 10855918)
Are you shitting me?

:rlaugh:

Bamato 11-10-11 08:11 AM

Didn't realize you had an aftermarket BOV. Check that too. Especially if it's a cheapo knockoff.

brian_skotch 11-10-11 11:06 AM

He checked most of the components and couldn't find the source. Thus why he's asking a question. Being an asshole and laughing doesn't help this thread at all. Only your post count. Please contribute.

anyways, my vote is you take that intercooler off and go over everything. make sure all of your couplers are tight too! Check your waste gate actuator and that it moves back and forth. If no luck there, tackle the bov.

Tyler [S5 FC] 11-10-11 06:11 PM

Sweet, I'll definitely check that stuff.

And the knock off bov sounds like thats my idling issue. When I bought the engine, it came with that pos bov and also a knock off $10 ebay boost controller. I've been meaning to replace both of those. I'll update this thread to let you guys know what the culprit is. Might be on monday though, have been working 11 hours a day this past week and don't have shit for energy when I'm off.

And I don't care if anyone laughs at my questions, in fact I'm glad my ignorance is at least amusing to someone lol. I find it a little funny how there are hundreds of little plugs and adapters and little things filling the engine bay, and some of you expect everyone to know every piece without any schooling, like its just common sense. But anyways, thats the internet for ya.


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