2001 Infiniti QX4 Needs a Fuel Pump

jigngrub

Fleet Admiral
Joined
Mar 19, 2011
Messages
8,155
Is anyone here familiar with changing the fuel pump on a 2001-03 QX4 or Pathfinder?

The Q died on the wife the other day when she was on her way to work. She commutes 2 hrs. one way and the darn thing died 1 1/2 hrs. away from the house:facepalm:. She limped into a dealership and they couldn't find the problem since the engine wasn't popping any codes on the computer. So the dealership mechanics pull out a dirty MAF sensor and tell her she needs an engine replacement.

The vehicle is 13 yrs. old and we weren't about to sink that kind of money into it so the wife buys a new Altima that she can pay for with the money she saves in MPG difference.

To get the Q home I rented an auto transport trailer from U haul which took 6 hrs. round trip (dammit man!)

So I've been futzing around working on the Q because I'm not convinced it needs a new engine. I replaced the spark plugs (major PITA) and the engines fires right up real good but dies after a few seconds, so the red flag goes up... it's in the fuel system.

Today I go out to change the fuel filter because it may be clogged (the wife is the worlds worst about using the cheapest gas). I didn't relieve the pressure on the fuel line on purpose so I could see if the fuel pump was still good. Wouldn't ya know that when I disconnected the fuel line from the filter what should have been but big burst of gasoline rushing out instantly when the line was pulled off the filter was only a mere trickle after I disconnected the line from the filter.

So I put a bucket under the disconnected line and turn the ignition key on, this should have sent a strong stream shooting out of the end of the hose... but again, only a mere trickle.

I've searched online for a video or thread on how to do this but have found very little help, only where the access hatch to the fuel pump is.

I want to check the pump and strainer and drain and clean the fuel tank as good as I can without dropping it.

Any help on this subject would be greatly appreciated.
 

windy5849

Petty Officer 1st Class
Joined
Aug 12, 2010
Messages
237
Re: 2001 Infiniti QX4 Needs a Fuel Pump

Have you checked the fuse and or relay for the pump? My wife had a 1996 Chevy Lumina with a bad pump. I found that if I hit the fuel tank with a rubber mallet, the pump would work until the car was turned off and the mallet was needed again to start it. We took it in and parts and labor were $300 (?) to replace it.
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,537
Re: 2001 Infiniti QX4 Needs a Fuel Pump

Does fuel come out when you crank?

Could you hear the fuel pump come on when you turned the ignition key on?

One way of troubleshooting this is to disconnect the fuel pump connector at the tank and power it with test leads to see if the car runs.
 
Last edited:

Bob_VT

Moderator & Unofficial iBoats Historian
Staff member
Joined
May 19, 2001
Messages
26,046
Re: 2001 Infiniti QX4 Needs a Fuel Pump

We had a run of BAD GAS years ago here and I actually worked at a nissan dealer. You have access to the fuel pump (INSIDE the tank) from under the rear seat. No need to drop the tank. A replacement as per rockauto is about $115 +/- for an exact replacement. Really not too hard to do.

Another good test is to get your ear near the tank and have the wife turn the key on...... you should hear a slight hum from the pump.
 
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