Lesson learned on Boost leak tests
#31
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I'm gonna have to do this before I get retuned. It has 56k miles on it with full boltons, cams, and FP Red turbo. My trap speed has always been on the low side with my previous tunes. This could be the source.
#33
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You might also have drilled/tapped your IM for extra boost sources. If it leaks under boost, it'll pull extra air in under vacuum and cause your idle to be high and/or setup incorrectly.
The superglue isn't really for fixing a boost leak, but rather to prevent an important vacuum hose from blowing off (such as the boost reference line on your fuel pressure regulator).
You can't be too **** on a boost leak test. The car in my signature (DSM 35r dyno record holder) would be tested to 50psi. If it doesn't leak at 50, it sure as heck ain't gonna leak at 30.
Be advised though, your intake tester can become a DEADLY projectile at 50psi.
Also, sealing up leaks at 50psi can take several hours.
#35
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+1 I almost lost a finger once at 25psi lol..
It's very possible the car is running much richer now with a fixed leak. You may have previously had artificially high load wheras now you will be running at a lower load path in the fuel and timing maps..
It's very possible the car is running much richer now with a fixed leak. You may have previously had artificially high load wheras now you will be running at a lower load path in the fuel and timing maps..
Yes, you absolutely sometimes will see air leaking from injector seals, or IM gaskets.
You might also have drilled/tapped your IM for extra boost sources. If it leaks under boost, it'll pull extra air in under vacuum and cause your idle to be high and/or setup incorrectly.
The superglue isn't really for fixing a boost leak, but rather to prevent an important vacuum hose from blowing off (such as the boost reference line on your fuel pressure regulator).
You can't be too **** on a boost leak test. The car in my signature (DSM 35r dyno record holder) would be tested to 50psi. If it doesn't leak at 50, it sure as heck ain't gonna leak at 30.
Be advised though, your intake tester can become a DEADLY projectile at 50psi.
Also, sealing up leaks at 50psi can take several hours.
You might also have drilled/tapped your IM for extra boost sources. If it leaks under boost, it'll pull extra air in under vacuum and cause your idle to be high and/or setup incorrectly.
The superglue isn't really for fixing a boost leak, but rather to prevent an important vacuum hose from blowing off (such as the boost reference line on your fuel pressure regulator).
You can't be too **** on a boost leak test. The car in my signature (DSM 35r dyno record holder) would be tested to 50psi. If it doesn't leak at 50, it sure as heck ain't gonna leak at 30.
Be advised though, your intake tester can become a DEADLY projectile at 50psi.
Also, sealing up leaks at 50psi can take several hours.
#36
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well im also at like 21psi now cuz I put a stock BOV and its leaking anything above 21psi until my IX gets here on tues.
i saw like high 10's at 21psi last night. Im not gonna stress it much though. Im getting retuned with cams and new injectors in the next few weeks.
#37
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when your TB seals are bad, how noticable is it on a leak test?
I just retested and dont hear anything from the injector seals. I think maybe I might hear a little something from the TB seals, but not sure. I deff cant feel anything.
Is it a good thing to just replace anyway?
Car has like 55k on it right now.
I just retested and dont hear anything from the injector seals. I think maybe I might hear a little something from the TB seals, but not sure. I deff cant feel anything.
Is it a good thing to just replace anyway?
Car has like 55k on it right now.
#39
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When I was doing the testing, the injector seal leak was not very loud at 10 psi. At first, I thought it was the throttle shaft seals. When I leaned over the motor to listen, I could feel the air from the injector seal on my face. Lightly wriggling the injector made it leak more depending on the direction I pressed. I raised the pressure in my compressor and I was able to briefly get about 20 psi. The noise was very noticeable at that point.
Incidentally, I used a tire inflator with a dial type pressure gauge built on it. That way I can see exactly what pressure is in the turbo system at all times during the test. The injector seal was leaking way too fast to get an accurate reading with a standard tire gauge
Incidentally, I used a tire inflator with a dial type pressure gauge built on it. That way I can see exactly what pressure is in the turbo system at all times during the test. The injector seal was leaking way too fast to get an accurate reading with a standard tire gauge