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The pump isnt working while you turn the key to On it only works when you turn your key to start. I am sure that sound comes from it. I will check cables and post a reply for you.

If it sounds when you turn the key to start, it's not the pump. It's the starter.

Daninski wrote:I'm curious as well, some cars the ignition and pump won't do anything till the crank sensor sees rotation.

This exactly.

There is NO mention of a "pressure sensing circuit" or a "priming circuit" anywhere in the manuals.

In fact, to test the pump, here's the procedure:

Priming the fuel system:

http://mx-3.com/manuals/showimg.php?fil ... F2-111.gif

checking the circuit opening relay->

http://mx-3.com/manuals/showimg.php?fil ... F2-117.gif

"Listen for the operational sound while the starter is operating"

The sound is comming from back.

Whether the pump primes the circuit or not has nothing to do with the discussion at hand. The pump does prime the circuit. If you do what I said before, you'll hear it. In any case, it makes absolutely no difference here.

If the pump does prime the circuit, it will run for a couple of seconds at the most, when you turn the key to "ON", and then it will stop. In NO CASE will the pump keep on running while you're trying to start the engine, if the engine is not rotating. The pressurizing of the fuel circuit is done prior to the engine cranking, so the fuel injectors will have enough pressure to work properly from the get go. Once the key is moved to the "start" position, the ECU will look for the signal that the engine is cranking, to start the fuel pump.

If it doesn't prime the circuit, obviously, you won't hear it, until the engine is cranking.

In any case, there's no way in hell the pump will run continuously while the engine isn't cranking, and there's also no way in hell I'm gonna spend the time to prove what the pump does or doesn't do. In any case, it's not what the OP is asking.

Daninski wrote:

Daninski wrote:I'm curious as well, some cars the ignition and pump won't do anything till the crank sensor sees rotation.

This exactly.

There is NO mention of a "pressure sensing circuit" or a "priming circuit" anywhere in the manuals.

In fact, to test the pump, here's the procedure:

Priming the fuel system:

http://mx-3.com/manuals/showimg.php?fil ... F2-111.gif

checking the circuit opening relay->

http://mx-3.com/manuals/showimg.php?fil ... F2-117.gif

"Listen for the operational sound while the starter is operating"

Umm, I never wrote the above bolded passage, so how did it end up under my name?

Daninski wrote:

Daninski wrote:

Daninski wrote:I'm curious as well, some cars the ignition and pump won't do anything till the crank sensor sees rotation.

This exactly.

There is NO mention of a "pressure sensing circuit" or a "priming circuit" anywhere in the manuals.

In fact, to test the pump, here's the procedure:

Priming the fuel system:

http://mx-3.com/manuals/showimg.php?fil ... F2-111.gif

checking the circuit opening relay->

http://mx-3.com/manuals/showimg.php?fil ... F2-117.gif

"Listen for the operational sound while the starter is operating"

Umm, I never wrote the above bolded passage, so how did it end up under my name?

https://en.wikipedia.org/wiki/Dissociat ... y_disorder

Ahahahaha... whoops, accidental moderator post

Ryan: your explanation makes more sense, but mine sounds better.

Thats true, but you're still wrong about the pump priming before the motor turns.

Pffffffftt.

Maybe I will try check ecu for errors. If it is the electrical problem ecu should give some error.

UPDATE.
I tried start engine by pulling my mx3 with other car, because I wanted check if this is the starter problem, what was strange that the car doesnt start, but when I tried hold the key on start position it starts and runs perfectly but if I release the key the car engine stops working ( like it doesnt get any fuel). I was writing above, that when I hold the key in start position I can hear the fuel pump sound, so I think it's the electrical problem, because ecu or smth. thinks that car engine doesnt started and the fuel pump doesnt work but if you hold the key it's working. Maybe it's the fuse's problem, I will try to change all fuse box with all fuse together, if you have any more ideas or suggestions please help me out

Checked the diagnostics, but it shows nothing, before all problems I was able to check errors by myself but now nothing shows up (I know that it have to show 1 error). Connected LED to FEN and B+ doesnt blink. So where can be the problem?

you're doing it wrong. No LED.

Jump GND and TEN with a paper clip or a piece of wire, turn key to ON, and look at CEL.