Fuel pump/Fuse blowing issue?

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x420BOOTYWIZARD
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Fuel pump/Fuse blowing issue?

Postby x420BOOTYWIZARD » Wed Mar 13, 2019 6:26 pm

Today my car died out (STOCK 240SX 1993 MANUAL SWAPPED) and I'm confused as to what the issue could be, story is I replaced my fuel filter as my friend suggested doing it as my car was acting weird felt like a lack of power and would hiccup rarely here and there. Once the fuel filter was replaced car took a bit to turn on but I assumed the lines needed to be filled again was all took about 10 solid tries though cranking the motor. Drove around and it was still feeling slower but didn't seem to hiccup. I parked it for a few hours and went to go start it again, started fine and all but I had to turn it off to go grab something and when I came back out it just would crank and crank with nothing happening, tried to apply gas and prime the pump multiple times. It was at this point I noticed I didn't hear the pump quite as much, eventually though the car did turn on but it was falling on its face and I needed to constantly apply gas to get it to run but eventually it died. At this point I started doing research and took a look at my fuse and relay and those were fine, I did notice my ENG CONT fuse was blown (no idea what that is but the car has been running fine no idea when it blew though). So I'm guessing its the pump? I just wanna confirm with some people who know there stuff before going and buying one. I'm not the most mechanically smart when it comes to cars, I'm learning slowly so please take it easy. I also searched through some of the posts here and have seen some similar issues but nothing along the same lines.


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AZhitman
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Re: Fuel pump/Fuse blowing issue?

Postby AZhitman » Wed Mar 13, 2019 8:44 pm

Odd that the pump would fail right after replacing the filter...

Did you remove the lines from the fuel rail when you changed the filter? I've seen someone reverse the lines, and that will cause the same symptoms.

x420BOOTYWIZARD
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Re: Fuel pump/Fuse blowing issue?

Postby x420BOOTYWIZARD » Wed Mar 13, 2019 9:02 pm

AZhitman wrote:
Wed Mar 13, 2019 8:44 pm
Odd that the pump would fail right after replacing the filter...

Did you remove the lines from the fuel rail when you changed the filter? I've seen someone reverse the lines, and that will cause the same symptoms.
No I left the lines on the fuel rail where they were, seemed odd to me as well.

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AZhitman
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Re: Fuel pump/Fuse blowing issue?

Postby AZhitman » Fri Mar 15, 2019 11:14 am

Next step, I'd test fuel pressure at the rail (the inlet is the one NOT by the regulator).

The regulator is on the return side.

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Re: Fuel pump/Fuse blowing issue?

Postby PapaSmurf2k3 » Sun Mar 17, 2019 3:13 pm

Yeah I'd replace that blown fuse and either pull a fuel line and key-on to see if the pump is actually pumping anything, or doing a fuel pressure check like Greg said.

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Re: Fuel pump/Fuse blowing issue?

Postby amc49 » Mon Mar 18, 2019 4:52 pm

If the filter was clogged completely then not odd at all for the pump to fail shortly after from being deadheaded all the time. Running at close to hydrolock kills them.

If pump seems to be changing noise then a pretty clear indicator it's going bad.

One of the biggest mistakes is running cars out of fuel and then trying to prime with say only one gallon of fuel in tank. It often tears up pump in minutes, they if a plastic impeller like most have maybe a solid minute of dry running before the impeller begins to melt and how so many get warrantied as 'bad' right out of the box. Yes, they're bad but because the user ruined them trying to prime with too little fuel. You should ALWAYS prime a pump with at least 3 gallons of fuel in tank to make sure the pickup strainer is COMPLETELY covered as partially covered they will suck air as it is easier to pull that than fuel. I used to warranty pumps treated like that all day long, typically more were ruined that way than by simply wearing them out. You can look up in the inlet port to see the melted impeller. Why all owner manuals now say to not run the car out of gas.

When priming listen to the pump, it will spin fast and as soon as it hits solid fuel it then lugs down to still spin but at a slightly slower rate.

Need a pressure check there, a pump can output what appears to be normal fuel amount with it just pumping into air but not output any when pressurized into the system. A worn impeller will move fluid all day long as long as the pipe is open ended. Close it and then the fuel simply backslips around the worn impeller edge to go nowhere. That can be very erratic to start and run but then it quits or otherwise acts funny, the problem will come and go.


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