Vehicle: 2003 Nissan Pathfinder (Applicable to all R50's, 1996 - 2004)

Officially, Nissan recommends changing the fuel filter when the Pathfinder doesn't respond well when you press the gas pedal. As a preventative measure, however, you should change your fuel filter on a regular basis. I recommend changing it every two years, as a preventative measure. Some change their fuel filters annually, other wait longer.

A clogged fuel filter can cause poor acceleration, rob power, and reduce fuel economy. Using a clogged fuel filter also puts a strain on the fuel pump and can cause it to fail prematurely.

Difficulty: 2 / 10 -- A little elbow grease needed, but not too difficult.

Tools Needed:

- Ramps, or a jack and jack stands- Wheel chocks- 10mm socket or wrench- #1 Phillips screwdriver- Eye protection is recommended.

Preparation: Raise the rear axle of the vehicle, either by backing onto ramps or jacking up the vehicle and using jack stands. Make sure to use wheel chocks in front of the front tires.

Step 1: Relieve fuel line pressure.

WARNING: The fuel lines are under pressure, and removing the hoses from the filter without relieving the pressure will cause it to spray everywhere.

The recommended way to relieve pressure in the fuel line is:

a) Remove the fuel pump fuse, found behind the coin drawer to the left of the steering wheel.



b) Start the vehicle. With no power to the fuel pump, it will quickly use up the fuel in the lines and then stall.

c) Crank the vehicle a few times to make sure the fuel is consumed.

Step 2: Locate the fuel filter

The fuel filter is located on the rear underside of the vehicle, above and in front of the rear differential. Note the orientation of the filter, as it is designed to have fuel flow in a specific direction.



Step 3: Remove the filter from the bracket.

The filter is held in place by a bracket with a 10mm bolt. Remove the bolt and open the bracket. Since it's exposed and on the underside, it will probably be quite rusty, so care should be used.

NOTE: If the hoses connected to the fuel filter are visibly cracked, you may want to use this opportunity to replace these hoses as well.

WARNING: Since the fuel filter is part of the fuel system, do not use a torch or other heat source to help loosen the bolt.



In my case, I managed to break the head off the bracket bolt.



Step 4: Remove the clamps and hoses.

The hoses on either end are held on by a clamp with a #1 phillips screw. Loosen the screw, then pull off the hose by hand (tools may damage the hose). The hose can be very tight; twisting it back and forth while pulling it off helps overcome the resistance.

Some residual fuel will leak out from the hose and/or filter as you remove each hose. Have some rags ready and be careful to not get any in your eyes or mouth.





Step 5: Attach the new filter.

Attach the filter in the same orientation the old filter was in. The fuel flows from the driver side to the passenger side. If your filter has an arrow on it, make sure it points to the passenger side. In my case, both filters had the rounded end on the driver's side and the flat end on the passenger side.

The screws on the clamps should be tightened from 8.7 to 13.0 in-lb.



I had to use zip ties to hold the bracket closed. I'll probably drill some new holes and do a more permanent fix later.



Step 6: Install fuel pump fuse, start engine.

Re-install the fuel pump fuse and start the engine. It may take a few cranks to re-pressurize the fuel system. Rev the engine a few times, and then check underneath for any signs of leaking.





Modified by Densetsu at 2:04 AM 11/2/2009
Modified by Densetsu at 2:08 AM 11/2/2009

isnt that bad to just let it run out of gasoline?

Great how-to! I did this about 5 months ago and I had to completely replace the filter bracket/clamp ($30 from the dealer) because my old one ended up getting completely destroyed when I tried to remove the bolt.

korbeano89 wrote:isnt that bad to just let it run out of gasoline?

Not at all. It's only bad when you're actually low on gas and it can suck any sediment from the bottom of your gas tank. In this case the engine just stalls. My car wouldn't even start when I did this, it just cranked a couple of times.

korbeano89 wrote:isn't that bad to just let it run out of gasoline?

not on an unleaded engine.

You never want to run out of fuel if you have a diesel engine. That is a real pain.

that i knew,it happen to one of my friends,it took awhile to get all the air out of the lines. just wasnt sure on unleaded.

I changed mine at 172km and now is 190km. Should i change it again?

JonathanPrem wrote:I changed mine at 172km and now is 190km. Should i change it again?

I personally think this should be a 12,000mi/12mo. maintenance item, especially if you always use every last drop of gas before refilling. The filters are super cheap and the job takes maybe 30 minutes (if the bracket is in good condition).

Excellent write up! We gotta add this to the "How To:" hopefuls. I changed mine a few months ago and wow those hoses are a b**** to get off. Luckily I don't have the rust issues you guys do and my bracket is still like new. Thanks for the contribution!

Billy

Pwnin O’Brien wrote:
I personally think this should be a 12,000mi/12mo. maintenance item, especially if you always use every last drop of gas before refilling. The filters are super cheap and the job takes maybe 30 minutes (if the bracket is in good condition).

I usually do it every two years, but I certainly wouldn't object to people changing them on an annual basis, or something like every 25,000km. The NAPA Gold filter I put in was $20, the NAPA Silver filter was something like $12. I know the gold one is made by Wix, not sure about the silver one.

I bought my Pathy two years ago, don't really know why I waited this long to change the fuel filter as I changed pretty much every other fluid and filter within six months of buying it. And the fuel filter I took out looks pretty old. I'm thinking of cutting it open and seeing what it looks like... with non-sparking tools, of course.

I do think that the Pathy seems to accelerate smoother now... though that could just be a placebo effect.

Thank you for posting this! It was perfect timing! Got er done!

My mounting bracket bolt was seized too! Darn rust! I just loosened it up enough and bent it open a little and slipped the old one out. Jammed and wedged the new one in and had to double link 2 zip ties around the bracket/filter to hold it in place.

Thanks again!

Thanks! for the write up..Made a huge difference! & Very Simple

x2. Great writeup. My bracket was rusted etc. If anyone is interested I can look for Nissan part no's for the bracket and filter. I think the filter was about $17 (mentally didnt want a store bought China filter like Fram etc, its a mental thing), and I think the bracket was around $18.

Thanks for this write up. I've been having weak acceleration and will try this on monday.

Always love how-tos w/ pictures.

Just another FYI for those looking into doing this.

Even with the fuel pump fuse pulled, gasoline will still trickle from the fuel tank side once the hose is disconnected from the old fuel filter.

I made the mistake of taking off the engine side first so then I had to fumble around to try to get the filter disconnected from the tank side while the thing was leaking gasoline.

My advise is to have a balloon or an extra glove ready and unplug the tank side first and then use the glove or balloon to block the hose from leaking and then take your time removing the engine side hose from the old filter as this line will be dry.

If you're under the car with your head pointing towards the front of the car and your feet sticking out the back of the car, the tank side is the left side and the engine side is the right side of the filter.

kkamakasi wrote:Just another FYI for those looking into doing this.

Even with the fuel pump fuse pulled, gasoline will still trickle from the fuel tank side once the hose is disconnected from the old fuel filter.

I made the mistake of taking off the engine side first so then I had to fumble around to try to get the filter disconnected from the tank side while the thing was leaking gasoline.

My advise is to have a balloon or an extra glove ready and unplug the tank side first and then use the glove or balloon to block the hose from leaking and then take your time removing the engine side hose from the old filter as this line will be dry.

If you're under the car with your head pointing towards the front of the car and your feet sticking out the back of the car, the tank side is the left side and the engine side is the right side of the filter.

I made the same mistake and ended up duct taping the leaking hose pointed up on something to stop the leak.

Apologies for the double post, but I found a great set of pictures of a cut-open fuel filter in this thread: http://www.bobistheoilguy.com/forums/ub ... er=2142141

Just goes to show that an often-overlooked maintenance item can cause issues and actually does something!

I was able to do this last night in about an hour... The stupid gas lines were a b**** and a half but they were the only hold up.

I pulled the fuse and let the car run til it died but a warning should be given as the passenger side will still have quite a bit of gasoline, around 2-3 cups worth. I ended up getting doused, haha.

Oh well. Job accomplished and the PFinder is running much more smoothly!

Opening the fuel tank cap before disconnecting the hoses from the filter also helps relieve pressure from the tank side.

I took my QX4 in to the oil change place i go to and they charged me $40 to install an OEM filter that i brought with me... they didnt do anything with the fuses, only the gas cap thing...

I just did this to my '04 Pathfinder. In the cold I was having rough starts, where it seemed the engine was starved for gas for the first couple seconds. That could have been a number of things, but I also noticed I couldn't get it over 5,000RPM. I'm normally not a leadfoot, so it took a lot of driving before I actually floored it and noticed this problem. I put two and two together, swapped out the fuel filter, took it on a test drive, and can easily get it close to redline now.

Just a couple of side notes from my second time doing this.

- In case it isn't obvious, it's a lot easier to do this if you first remove the spare tire. Gives you much easier access to the filter.

- Unlike my last Pathy, with this one the bracket bolt actually came out without breaking. I did notice, however, that the top half of the bracket was starting to shear as I undid the bolt more and more. Using a pair of vice-grips and clamping the two halves of the bracket together solved this problem; it might have broken the bracket eventually. Alternatively, you could try to get a socket or wrench on the nut on the top of the bracket, but given the tight space, vice-grips is an easier solution.

When I changed my fuel filter I got one from NAPA for $7 (NAPA Silver, maybe?). Since I'll be changing the fuel filter yearly, is there any downside to using this cheaper filter vs. the $14 OEM filter or a NAPA Gold (Wix) brand filter? I don't know how much the NAPA Gold filter costs, I'll find that out in May when I'm choosing the next fuel filter.

Is there a torque spec for the filter bracket itself? I can't find one in my year FSM.

And I'll definitely remove the spare tire next change - I'm so small that I can sit upright underneath the back of the vehicle with the spare removed, which will make things a whole ton easier. The first change I crawled underneath and faced toward the rear of the vehicle, which was a PITA. I also definitely noticed a difference after changing out the fuel filter, can achieve higher RPMs much easier now. The filter might have been changed once before by some shop as part of their fuel system tune-up or something like that, so I wasn't using the OEM filter.

I changed my fuel filter earlier today. Got a NAPA Gold 3023 (Wix 33023 rebranded) for $13. Depressurized fuel system by removing fuse, turning key to "ON" then starting the vehicle. It died almost immediately. Removed gas filler cap, cranked a few more times. Removed spare tire, sat under trunk and swapped out fuel filter. The hoses were a bear to get off. I removed the filter from the bracket and then twisted the hoses for like 15 minutes to get them both off. I got the driver's side hose off and then plugged it with the new filter, then the other hose. The passenger side hose was more difficult to get off, requiring a lot more twisting at the hose. My right hand actually blistered a little from it. The old filter was a NAPA ProSelect.

Anybody have any tips on removing the hoses easier?

lol this is how i removed the old filter,

held the fuel filter tightly with one hand, then used the other hand to keep twisting the hose, no pulling, just twisting, then when it started budging, thats when you start puling while twisting.

MOST IMPORTANT: wear gloves, something like mechanix

That's what I tried, but without some good gloves that just eats up the skin of your hands! I used a paper towel for extra surface area, and boy did that hurt even more. Eventually got them off that way. I'll make sure to pick up some good gloves in a year when I change it again.

m0nkeyprince wrote:lol this is how i removed the old filter,

held the fuel filter tightly with one hand, then used the other hand to keep twisting the hose, no pulling, just twisting, then when it started budging, thats when you start puling while twisting.

MOST IMPORTANT: wear gloves, something like mechanix

--Very handy information, thanks!

I just swapped out my fuel filter. I have no idea if it had ever been changed out or not!

Dang if it didn't take a long time to get the lines off of the filter!

Notes:

I didn't have to jack up my pathfinder, but I have a rear tire carrier (so no spare underneath). I also have rear air helper springs. Enough room underneath for me to work allrite.

I did end up grabbing a foam block I had lying around to help support my neck because it took so darn long to pry off the one fuel line.

I disconnected (pulled out) the fuel pump relay and cranked the engine to depressurize. The fuel pump relay for my year (1999.5) is in the fuse box rite near the battery.

As other folks mentioned there still is a bit of fuel in the line after depressurizing. I found some vacuum line caps in the bottom of my tool kit, and used one on the open end of the old fuel filter once I got one fuel line off. Worked a charm, and then I could twist the old fuel filter without dripping gas all over.

I never could get the nut/bolt off of the retaining ring, but the ring was loose enough that I could wriggle the filter out, as well as the new one in. I used some heavy pliers to give the retaining bolt/ring just enough of a twist so that the new filter will not budge.

I think spraying a touch of penetrating oil on the end of the fuel line really helped getting it to turn. I figure some got on there anyways when I shot the fuel line clamps, so after a while of trying to get it to turn I shot some rite at the end of the line. Started turning nearly rite away after directly shooting some on there.

Camelfilter wrote: but I have a rear tire carrier (so no spare underneath).

Is that after market or did you swap it from a earlier year? I've never seen a r50.5 with a rear tire carrier

Chris.m wrote:

Camelfilter wrote: but I have a rear tire carrier (so no spare underneath).

Is that after market or did you swap it from a earlier year? I've never seen a r50.5 with a rear tire carrier

I don't think it's aftermarket (not sure). Dealer option maybe?

I'm the original owner, and the dealer installed it when I bought the truck. The dealer also installed a bull bar/pushbar.

Camelfilter wrote:

I don't think it's aftermarket (not sure). Dealer option maybe?

I'm the original owner, and the dealer installed it when I bought the truck. The dealer also installed a bull bar/pushbar.

Does the back look like this;? (JDM Terrano)



or is it mounted off the tow hitch?

Chris.m wrote:

Camelfilter wrote:

I don't think it's aftermarket (not sure). Dealer option maybe?

I'm the original owner, and the dealer installed it when I bought the truck. The dealer also installed a bull bar/pushbar.

Does the back look like this;? (JDM Terrano)



or is it mounted off the tow hitch?

Yeah, my tire carrier looks similar to the one pictured. It swings out so the tailgate can be lifted.

....Hmm let me see if I can wield the wonders of the web and post a picture of my truck...



Uploaded with ImageShack.us

-Had I kept my witts about me when I bought the truck, I would have tried to have the dealer include the spare underneath. Would have made the tires last longer (easier to rotate).