No Primary Boost?? but secondary...
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No Primary Boost?? but secondary...
I have no boost on the primary turbo, well it does show like 2lbs sometimes, but the secondary comes on strong. I also noticed a difference in exhaust tone when the primary should be on.. It sounds a little more lower pitched than normal. I allways thought that the primary had to boost 8lbs for the secondary to come on, but i guess this is an exception. Does any one know what this could be?
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The 8lbs rule only really applies to "Fast Transition" between primary, and secondary combo. The fact that you are getting boost from secondary would indicate that your vacuum side of the turbo control actuator is working well.
The poor primary could be a number of things like a broken waste gate. Actually, I think that the waste gate would be the only thing that would cause what your are seeing. Check out the waste gate actuator and look to see that:
a. The Actuator rod is attached to the waste gate valve on the turbo manifold and...
b. That the waste gate actuator isn't fully extended and non retracting.
The poor primary could be a number of things like a broken waste gate. Actually, I think that the waste gate would be the only thing that would cause what your are seeing. Check out the waste gate actuator and look to see that:
a. The Actuator rod is attached to the waste gate valve on the turbo manifold and...
b. That the waste gate actuator isn't fully extended and non retracting.
#3
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It sounds like a sticky wastegate or solenoid. You can't get secondary boost without primary boost, and the wastegate starts moving around at 4500rpm...
Have you checked the actuator and the solenoid?
Have you checked the actuator and the solenoid?
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i had similar problems. intermittently i would have no primary boost, seconardy boost would be fine. I replaced all of my vacuum hoses and now my boost pattern is perfect . There were a few hoses that were crimped, but I think the cause of my problem is that the hose from the y-pipe to the vacuum chamber did not have a check valve on it (stupid mazda dealers).
good luck
good luck
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Well as strange as it came the problem just disappeared... For now anyway. Hopefully for good. If it happens again which is inevitable I check the solenoid and actuator. Thanks for the replys.
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Originally posted by Flybye
...You can't get secondary boost without primary boost, and the wastegate starts moving around at 4500rpm...
...You can't get secondary boost without primary boost, and the wastegate starts moving around at 4500rpm...
#7
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The turbo control actuator uses primary boost and vacuum to open up to allow additional exhaust to flow to the 2nd turbo. Boost alone isn't enough to open the control valve all the way. Don't ask me why Mazda did it this way :p
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I just went throught this -
i was getting about 1psi on primary and max on secondary.
replaced the turbo control solenoid (the one with 2 lines coming out of it and under the manifold) and all problems fixed.
good luck
i was getting about 1psi on primary and max on secondary.
replaced the turbo control solenoid (the one with 2 lines coming out of it and under the manifold) and all problems fixed.
good luck
#10
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Originally posted by silver93
I just went throught this -
i was getting about 1psi on primary and max on secondary.
replaced the turbo control solenoid (the one with 2 lines coming out of it and under the manifold) and all problems fixed.
good luck
I just went throught this -
i was getting about 1psi on primary and max on secondary.
replaced the turbo control solenoid (the one with 2 lines coming out of it and under the manifold) and all problems fixed.
good luck
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