HELP! Turbo won't run after new fuel rail!

tekguyonroad

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I just replaced my leaking fuel rail (billet tees and stock injector caps) with a billet fuel rail. There were 3 billet tees. One was fuel in, one was to fuel pressure gauge, and one fed the secondary billet fuel rail (Stage 2 RCC). The new primary billet rail only has 2 ports. I plumbed it as follows. Inlet from the pump on the left primary. Outlet of primary to inlet of secondary. This line has a tee to feed the fuel pressure gauge. Outlet of secondary rail to a Bosch unit which I assume is a pressure regulator as it has a vacuum line attached which leads to the bottom of the airbox. As far as I can see the only difference is the f.p. gauge is feed off the line from the primary rail to the secondary rail. Here's the symptom: when I turn on the key the fuel pressure reads 30psi (normal). When I start her the pressure goes to 100 (pegs the gauge). She doesn't run particularly well, won't rev past 4k and won't build boost. There are 2 vacuum lines on the bottom of the airbox: one goes to the tail of the bike and connects to a small black box that has a label 091906 0652 part 12223861 and a lot id number. The wiring from this module goes to the MT2 controller. The other line I already described (goes to the Bosch unit). The line that goes to the boost gauge is actually tee'd with the other line going to a throttle body. The other vaccum lines I see are all tee'd to the 4 throttle bodies and connect to a single line which feeds to what looks like a filter and tee'd off to a Suzuki component with the part number 15620-02F00. All I did was replace the stock rail (with billet inserts) with a billet rail. What the hell did I do wrong? Thanks,
Hank
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Your base pressure should be 43 psi. Your pressure shouldn't go up when you start the bike and idle, if anything it might drop a couple psi.
 
Before the rail install the pressure was 30 psi all the time. Now, when I turn the key the gauge shows 30 psi but when I start it it jumps to 100 psi. What controls the fuel pressure? the Bosch unit? where does the control signal come from? Are the two fittings in the airbox the same? It does it with the tank down as I'm usually going for another test ride in the parking lot.
 
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sounds like your return line is pinched, did you change the fuel line routing to the regulator and got the inlet mixed up with the outlet and the return?
 
busa2001 wins. I got up at 7 this morning and started wrenching on her again. I found the pinched return fuel line. It makes sense now. Hindsight always does!
Thanks,
Hank, Redwood City, CA
 
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