barely building boost with ebay turbo
#1
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barely building boost with ebay turbo
As the title says, i'm barely building any boost (no matter what i do with the MBC) with my 92 that has an ebay turbo with an internal wastegate. I've searched high and low for boost leaks and cant find any, although there is a slight hiss near the intake manifold. i can't remember if that hiss was always there or if it started around the same time as the boost drop. also it doesnt seem like a boost leak to me since it hits the same 18 in/hg of vacuum as before. i also haven't been able to spot any exhaust leaks before the turbo. i even changed the manifold to turbo gasket just to be safe, to no avail. there is no smoke from the tailpipe so i wonder... is my ebay turbo finally blown but the oil seals are ok? or is that not even possible?
EDIT: forgot to mention that the wastegate has two nipples on it. the upper one I can't blow into, the other blows right out by the rod with hardly any resistance. i can switch the vacuum line with my MBC on it from one to the other and it makes no difference whatsoever.
EDIT: forgot to mention that the wastegate has two nipples on it. the upper one I can't blow into, the other blows right out by the rod with hardly any resistance. i can switch the vacuum line with my MBC on it from one to the other and it makes no difference whatsoever.
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wouldnt vacuum reading be different though? i guess i'll have to build a boost leak tester... I was trying to avoid that.
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i've checked all the couplers, none have any tears/holes, and all of the pipes are in their couplers fully. and i tried changing the manifold to turbo gasket just to be safe even though it didnt seem to be leaking.
full boost is about 7 psi.
#14
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wastegate is 7 psi, i had bumped it up to 9 at one point but realized it was probably a bad idea and turned it down. it would have made more sense to just remove the MBC i know, but i wanted to have the option to turn it back up.
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EDIT: now that i think about it, the rod was pulled out a little bit with the flapper as closed as it would go. i figured that was supposed to be like that for more tension on the flapper making sure it was closed. was i right with my assumption or is my wastegate most likely not closing all the way?