start up problems again
Does the grey wire drop to zero after 2 seconds?
Purple wire is reference voltage from the PCM, a tad high, but it is what it is.
The 2 black wires: Need to know resistance to ground, not voltage. DVOM probe on one wire, and the other probe to chassis ground. Check both black wires the same way.
Black probe to chassis ground and red probe to black wires, voltage should be zero.
Purple wire is reference voltage from the PCM, a tad high, but it is what it is.
The 2 black wires: Need to know resistance to ground, not voltage. DVOM probe on one wire, and the other probe to chassis ground. Check both black wires the same way.
Black probe to chassis ground and red probe to black wires, voltage should be zero.
Ohms is how much resistance there is through a wire. The lower the better. If a wire is partially broken, corroded, or there's a poor connection, it will have high resistance. The higher the resistance is, the less efficient the load, (fuel pump in this case) will operate. If the wire is completely broken, resistance will be infinite, and the load will not operate at all. In your case, we're suspecting higher resistance, but not infinite because the pump at least works. Probably a poor connection somewhere, and hopefully the pump works properly after you soldered the connections. That might be all it is/was.
If fuel pressure is still not good, the next set of tests, before the tank and pump go back in, is Voltage Drop Testing
If fuel pressure is still not good, the next set of tests, before the tank and pump go back in, is Voltage Drop Testing
If the voltage drop test that you did in post #20 was good when tested at the fuel pump, both ground and positive, then the fuel pump is faulty. There are two connections inside the pump module. The wires run from the module connector to the fuel pump motor, if either of those connections is poor, (might be worth checking) it should have shown up on the voltage drop tests... if they were done correctly
Also check the short rubber hose from the pump motor to the module for fuel leaks. If all that stuff checks OK, replace the pump.
Also check the short rubber hose from the pump motor to the module for fuel leaks. If all that stuff checks OK, replace the pump.



