FUEL PUMP WORKS WHEN IT WANTS TO!!!
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FUEL PUMP WORKS WHEN IT WANTS TO!!!
Hey all I’m new to this forum, I’ve got a 98 civic sedan and my fuel pump doesn’t prime right away and I’m ready to take my car to the derby because of it, I already replaced the main relay, fuel pump, and fuse and still have the same issue, would it be a wiring issue? If so where would I start to run new wires? Thanks in advance
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Re: FUEL PUMP WORKS WHEN IT WANTS TO!!!
Check the ECU grounds.
If the CEL stays on when you turn the key on and don't crank, and the fuel pump doesn't run, and you're sure the main relay, grounds, and fuses are good, it could be a bad ECU. One common thing for a bad ECU to do is not turn out the CEL or prime the pump until after the key has been on for several seconds or even minutes. Then the ECU finally boots up and the car can be started.
If the CEL stays on when you turn the key on and don't crank, and the fuel pump doesn't run, and you're sure the main relay, grounds, and fuses are good, it could be a bad ECU. One common thing for a bad ECU to do is not turn out the CEL or prime the pump until after the key has been on for several seconds or even minutes. Then the ECU finally boots up and the car can be started.
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Joined: Apr 2013
Posts: 75
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Re: FUEL PUMP WORKS WHEN IT WANTS TO!!!
Check the ECU grounds.
If the CEL stays on when you turn the key on and don't crank, and the fuel pump doesn't run, and you're sure the main relay, grounds, and fuses are good, it could be a bad ECU. One common thing for a bad ECU to do is not turn out the CEL or prime the pump until after the key has been on for several seconds or even minutes. Then the ECU finally boots up and the car can be started.
If the CEL stays on when you turn the key on and don't crank, and the fuel pump doesn't run, and you're sure the main relay, grounds, and fuses are good, it could be a bad ECU. One common thing for a bad ECU to do is not turn out the CEL or prime the pump until after the key has been on for several seconds or even minutes. Then the ECU finally boots up and the car can be started.
I had the same issue. It is failing or out of spec electrolytic capacitors inside the ECU control board, they are replaceable but you must know how to disassemble the circuit board and solder. Usually if you inspect the PCB inside the metal ECU container you will see electrolytic caps that are leaking or bulging or both sometimes the gel material will just dry out and there are no obvious things to see on the cans...they are the weak link in all electronics even today they last at most about 25 years or so.
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Joined: Jan 2018
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From: Mississippi
Re: FUEL PUMP WORKS WHEN IT WANTS TO!!!
BINGO!
I had the same issue. It is failing or out of spec electrolytic capacitors inside the ECU control board, they are replaceable but you must know how to disassemble the circuit board and solder. Usually if you inspect the PCB inside the metal ECU container you will see electrolytic caps that are leaking or bulging or both sometimes the gel material will just dry out and there are no obvious things to see on the cans...they are the weak link in all electronics even today they last at most about 25 years or so.
I had the same issue. It is failing or out of spec electrolytic capacitors inside the ECU control board, they are replaceable but you must know how to disassemble the circuit board and solder. Usually if you inspect the PCB inside the metal ECU container you will see electrolytic caps that are leaking or bulging or both sometimes the gel material will just dry out and there are no obvious things to see on the cans...they are the weak link in all electronics even today they last at most about 25 years or so.
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From: The South - Roll Tide !!!
Re: FUEL PUMP WORKS WHEN IT WANTS TO!!!
The original power caps inside an OBD-1 ECU were designed to last 8,000 to 10,000 operational hours. Since most ECU's have reached this operational period, this type of failure will become very common.
Re: FUEL PUMP WORKS WHEN IT WANTS TO!!!
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