Why does my car make no boost with the wastegate safety-wired closed?
#1
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Why does my car make no boost with the wastegate safety-wired closed?
Just curious.
Came around a corner sideways in 1st last Thursday with my old T25, hit 2nd, and had no boost. I was planning to change the turbo anyway, so I did the swap to a GT2554R, but kept the old wastegate actuator. No boost. Then I switched to a new actuator, no boost. Then I wired the ******* wastegate closed, no boost. What gives? The only thing I can think of is that my EGR has somehow failed (I have a BEGI manifold with the EGR hooked up) and all the exhaust gases are rushing through there. I'm stumped, though; I figured wiring the ****** would give me at least a few PSI on roll-on.
Came around a corner sideways in 1st last Thursday with my old T25, hit 2nd, and had no boost. I was planning to change the turbo anyway, so I did the swap to a GT2554R, but kept the old wastegate actuator. No boost. Then I switched to a new actuator, no boost. Then I wired the ******* wastegate closed, no boost. What gives? The only thing I can think of is that my EGR has somehow failed (I have a BEGI manifold with the EGR hooked up) and all the exhaust gases are rushing through there. I'm stumped, though; I figured wiring the ****** would give me at least a few PSI on roll-on.
#4
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The WG flap is still on my T25. It's not a boost leak because my car sounds like a ******* Mack truck spooling up. I can't hear the exhaust over my turbo noise normally, and right now there is NO turbo noise. All the basic ideas get shot to hell by the fact that I've changed the turbo and wastegate actuator.
How do I change the god damn EGR? I don't even know how it works. >.<
How do I change the god damn EGR? I don't even know how it works. >.<
#5
Kinda greek to me as well. Isn't there an EGR valve on the intake manifold that open's and closes relative to vacuum. The valves stick sometimes and I think you can clean them with brake cleaner or something to unstick them. (doing research)
My egr is replaced with a block offplate on the back of the intake.
http://forum.miata.net/vb/showthread...ight=stuck+EGR
My egr is replaced with a block offplate on the back of the intake.
http://forum.miata.net/vb/showthread...ight=stuck+EGR
#10
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actually this just happened to me like 2 days ago and the turbo would not audibly spool when the pipe blew off. I suppose with the lack of actual boost increasing the exhaust pressure, it just cant quite get spinning quick enough.
#12
id also say check your pipework, if you have a cooler check that you havent got a hole in it also...... but in saying that you would normally hear a pipe come off or a cooler pop, it sounds like something poping & its loud, this happened to me once on my rx7 & trust me you know about it, in fact the pipe that came off did so with so much force that it dented the strut tower that it hit....
#17
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cracked mani/open pcv/blown hg, etc the car would still make SOME boost. even with everything functional and a tied open WG, it should still make a little positive pressure.
best explaination for no boost at all is a problem in the charge pipes.
best explaination for no boost at all is a problem in the charge pipes.
#18
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I had the manifold off extracting a stud when I changed turbos. I did not see any blatant cracks; I would think a problem so serious that it wouldn't spool the turbo would come up as a really ******* loud exhaust leak. The car sounds normal, mabye a tiny bit louder. Certainly not exhaust-leak loud.
#20
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I just drove the car and pushed it pretty hard. I can get to around 3psi at 5000rpm. There are no charge pipes broken; I pulled on them all pretty hard and none came loose in my hand. The wastegate is still wired closed. It makes boost VERY slowly, which leads me to believe that the pressures in the EM and the IM are constantly trying to equalize.
How hard is it to block off the EGR? Can I block it off and have no issues if it has really failed?
Does a 1.6 have an EGR? I have a salvage 1.6 that used to have a turbo, and I cannot see an EGR tube on it. If I can find the EGR on that motor, I can use its blockoff plate, possibly?
How hard is it to block off the EGR? Can I block it off and have no issues if it has really failed?
Does a 1.6 have an EGR? I have a salvage 1.6 that used to have a turbo, and I cannot see an EGR tube on it. If I can find the EGR on that motor, I can use its blockoff plate, possibly?