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mark houghton mark houghton is offline
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Join Date: Jul 2008
Location: Central Washington State
Posts: 3,776
I would agree with Mooney's input. But with your comment about engine vacuum being virtually nonexistant (is this presumption, or can you not feel any air being drawn down through the metering plate?). If no air, then read on:

The metering plate is the first place the intake air passes through, so it must deflect the plate unless the plate is stuck (which you say is not the case) or system fuel pressure is way too high.

Here are some exploratory questions that may seem condensending, but we need to know for sure (in answering, it's ok to say "well....DUH!!):
- Do you have a turbocharger hooked up (and all associated plumbing)? All the way from the rubber elbow connected to the metering plate housing, which in turn connects to the boost recirculation manifold "T" coupler, then on to the pipe and rubber couplers leading down to the turbo intake. The engine vacuum uses the turo and plumbing as the pathway to the metering plate housing.
- You do have the intercooler attached? If not, then all the air will be drawn directly through the throttle body instead of through the metering plate.
- Are both end caps present on the boost recirculation valve (the piston valve), and is the large (1/2" or so diam.) vacuum hose that attaches to the top cap of the recirc. valve hooked up? It's other end goes straight to the intake manifold post-throttle body, and if it was off you would suck all your needed engine air through that hole instead of across the metering plate.

You've gotta be sucking huge air somewhere. If that's not it, then it has to be your metering plate is not moving as freely as stated. Hang in there, the solution is just around the corner!
Mark H. 1987 930, GP White, Wevo shifter, Borla exhaust, stock everything else. The result of a massive Pelicanite good will fire recovery effort. Truely an open book, ready for the slippery slopes to modification.
Old 04-09-2010, 11:12 AM
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