A month back I installed a digital fuel pressure (FP) gage and when the car died due to low and then down to no fuel pressure, I suspected the fuel pump. I confirmed that the fuse was good and replaced the pump. Turned the key and nothing. I failed to check for the presence of voltage at the pump connection. Idiot. Must have been the relay. So I reach up behind the AC and un-clip it. Bench test it w/ a 9v batt and ohm meter. Test ok! Hmmm, Still no power at the pump. Well lets plug it back in and check for bad connections on the molex plug. Then I notice that when the FP relay was energized the 12v side leaving the relay was @ 5v. Turn the key off and check the hot side of the relay and it reads 12v. At this pointe I'm speaking in Tongues and I'm pretty sure that I ended up in a Fetal position. What in the Hell is going on? Then I remembered what that relay served. This little Bastard. The fuel pump controller.
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So I dropped the AC and pulled the console just to access the FPC. It was in a great place before I added AC. Once I removed the controller from the circuit I got 12v at the relay outlet. All of the turbo WRX's used one but only one Subaru EZ30 used one; mine, the 2003 YM. I had noticed that my fuel pressure varied with acceleration and that's what these do. I looked into bypassing the controller but decided Subaru knew better than I so $160 later I'll have one in a few days. Because mine is a "one year only" I had to order from the dealer. Otherwise, they're $35-$45 a pop on Ebay.
The carnage. Not as bad as it looks. I can have it back together in an hour.
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