Fuel Pump Fuse Keeps Blowing on Maxima

[1993_VG30E_GXE]

Curious what you guys think to the lifespan of those fuel filters. The car was sitting over the winter, and it did have Stabil in the fuel, and I just ran this car about 500 KM OK, but I notice that it has been getting a tad weak during starting, like the fuel could not be getting through?

Anyhow, it's very damp out and has been raining for 2 days now. I go to run it now and it ran for 10 seconds then died fast, fuel pump stopped and fuse blew. Waited a few minutes, put in another fuse, and it blew too.

It's a new fuel filter as of NOV 2009. I drove it around for about a month. Then it went to storage for 5 months.

Any other suggestions what could immediately cause the fuse to blow like this? Note that when I put the key into the ON position, I don't hear the pump functioning sound.

1. Faulty Fuel Pressure Regulator?
2. Faulty Wiring?
3. Corrosion in Gas Tank clogging Pickup Strainer on Fuel Pump?

Any other ideas?

 

[JHZR2]

Somebody on here once said that it is smart to use an underrated fuse on the fuel pump circuit. As the fuel pump wears and gets older, its draw will increase, and the blown fuse will be an indicator.

I'd say that if that is truly a scenario, then the fuel pump is worn sufficiently that it is in need of replacement.

Have you ever changed the fuel filters? Any reason to think the tank screen is in bad shape? Is the tank vent system working OK?

 

[Colt45ws]

Likely faulty wiring or bad pump. If you can get to the pump harness wiring, I would use a dmm there to check for a short between hot and ground along with checking the wiring. Then if that checked out I would ohm the pump.

 

[toyota62]

Disconnect the fuel pump wiring connector at the fuel pump and replace the fuse if fuse still blow then you have a shorted fuel pump power supply wire some where in the car or another electrical circuit getting power through the fuel pump fuse but highly unlikely.
If fuse doesn't blow then reconnect the fuel pump wiring connector and cycle the ignition switch to activate the fuel pump.If fuse blows then you need a new fuel pump.
Also you can check the fuel pump resistance to see it is shorted internally.Low resistance indicate internal fuel pump winding shorted each other.
If pump is defective make sure renew the fuel filter as well.
Cheers.
Bob.Oz.

 

[toyota62]

normal all automotive fuses are rated 3-4 time more than the circuit's current draw.All other circuits will have a circuit breaker instead of a fuse.Ex;power window,power seat's and sunroof circuit's.

 

[Audi Junkie]

Motors draw more current as they age. I'd slap in the next higher fuse and carry a spare.

 

[toyota62]

If OEM fuse blows, must not replace with a higher amperage fuse.All automotive fuses 3-4 time higher than the circuits current draw.
I learnt this when I was worked at GM,Holden and Toyota.
Ex;AC blower fan fuse rated 30A normal current draw in that circuit is 6-10A.

 

[toyota62]

Get a amp meter,prefer digital. remove any fuse from your fuse block and connect the amp meter across the fuse holder terminals turn the device that power up the fuse.you see what I mean.make sure power consumption must not exceed the amp meter power rating.

 

[1993_VG30E_GXE]

Thanks everyone, here's some responses:

JHZ: Fuel pump was replaced with new OEM Bosch #E3000-163020 - this pump was a rip - like $365.00

The pump was installed in FEB 2008 and has 18,253 KM on it up to today. When the mechanic installed it back then (because I didn't know car stuff back then), the wire loom is kind of loose flopping around under the seat. It's the in tank type pump and the tank is under the rear seat. The loom that holds the wires from the back of the car runs up the side of the rear wheel well on the insdie.

The rear wheel wells have large rust holes in them where rain water can enter and possibly spray the loom by looking (I should take a photo for you guys). It has been raining for 3 days, but I was driving the car in the rain for a day.

The fuel filter was last replaced NOV 2009 and has 1,624 KM on it.

This exact same scenario happened last fall before I put it away for storage, and when I replaced the fuel filter in NOV 2009, the car started immediately and the problem went away.

I just don't see how the filter would clog at 1,624 KM if the car sat for 5 months with a full tank of gas and stabil.

It's possible that the fuel filler neck is rusting and rust debris is going into the tank, but I'm not certain. Looking at the tank from underneath I don't see TOO bad rusting, but there was some rust development.

I should look at the tank screen, but the engine rebuilder I just talked to said if there was rusty chunks clogging the 'sock', it would likely fall as soon as you turn the car off.

The vent hose for the tank is disconnected, I just have the short half foot hose dangling on the side of the tank. It normally connects to a pipe that runs along beside the fuel lines and connects to the carbon canister which feeds to the engine I think to burn the vapors, but I didn't bother installing that pipe to save me time.

Colt - I'll check the wiring as you say.

Toyota62 - thanks for the detailed instructions I want to do this.

Do you guys think by some bizarre reason that it could be the fuel filter AGAIN? Last time the exact scenario happened a new filter fixed it.

I can say for the last week I have been getting strange starting symptoms like low fuel was getting to the chambers, and it wouldn't start on the first go. I would sometimes wait one minute and try 3 times then it would start. And I know it's NOT the starter, it too is a brand new starter.

 

[1993_VG30E_GXE]

UPDATE:

So I removed both back seats to do a visual inspection of the wires to the fuel pump. I don't see any visual signs of bare wire or any cracks in the insulation. I did move the wires around a bit checking all sides.

There is no water in the back as I patched those wheel well rust holes back in the winter temporarily with duct tape until I weld them, so no water came into the back seat.

I put in a 3rd fuse brand new, and the car starts and is now idling. I'll see how long it idles for.

Very strange indeed and not good, if I drive some long distance away what if the fuel pump just suddenly dies while I'm on the highway.

Given this new information, do I still do each of the tests you guys suggest?

There is a section of the loom that goes along the floor on the side of the floor board, that goes to the front but it's under the carpet. There is slight dampness in this corner of the floor board, but I would think the loom and insulation would nullify the dampness.

 

[Colt45ws]

I would still check for the very reason you mentioned. Blowing the fuse is not normal.

 

[1993_VG30E_GXE]

Very bizarre Colt. It just blew another one again. I then went and jiggled the wires, the unplugged then plugged back in the fuel pump, then put in a new fuse, and it blew the new fuse again.

I notice that it idles quite high immediately when the car turnes on, then dies from there.

I'm going to try and remove the fuel filter and blow it out with a compressor to see if anything is clogging it. I looked at the wires, and they didn't look damaged. Could it be the relay in the trunk?