Voltage drop on the 01 Camaro SS
#21
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Update on the voltage issue:
Positive side I'm getting 12.36 volts on power wire at the pump but when keyed on I'm seeing 1.2 volts and about 1.3 when running. Should be no more than 0.5 V so problem number one. On the negative side I'm getting a negative 1.8 volts when keyed on and running and it should be no more than 0.5 volts.
Positive side I'm getting 12.36 volts on power wire at the pump but when keyed on I'm seeing 1.2 volts and about 1.3 when running. Should be no more than 0.5 V so problem number one. On the negative side I'm getting a negative 1.8 volts when keyed on and running and it should be no more than 0.5 volts.
#22
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Update on the voltage issue:
Positive side I'm getting 12.36 volts on power wire at the pump but when keyed on I'm seeing 1.2 volts and about 1.3 when running. Should be no more than 0.5 V so problem number one. On the negative side I'm getting a negative 1.8 volts when keyed on and running and it should be no more than 0.5 volts.
Positive side I'm getting 12.36 volts on power wire at the pump but when keyed on I'm seeing 1.2 volts and about 1.3 when running. Should be no more than 0.5 V so problem number one. On the negative side I'm getting a negative 1.8 volts when keyed on and running and it should be no more than 0.5 volts.
You're seeing a 1.2vdc voltage drop?
Either way, I'd start with the FP relay. You're switching the positive side of the FP, correct?
Many times I've seen relay contacts being resistive (intermittently at times) cause this issue, as well as on the coil side of the relay. Analog 12vdc relays will attempt to function at about anything about 6-8vdc, just not very well.
#23
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#24
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I've made new connections for power and ground on the Racetronix harness and for both fuel pump connections. I still am getting 0.9V drop on the power side for both pumps and 0.2-0.3V drop on the ground side so it looks lke the ground side is now within the 0.5V but I still need to track down where this drop is occurring on the power side. I can try replacing all of the relays to see if that solves the issue but first I'm going to run a voltage drop test at the relays on the fuel pump wire harness.
#25
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Voltage drop between the postive on the alternator and battery was 1.5V with the negative side being 0.2V. Both should have been no more than 0.5V. So frustrating trying to figure out electrical issues.
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POS alternator is going back for a refund.
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#28
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Problem appears to be resolved.