i have a 98 f150 4.6 liter 4x4 supercab xlt

how can i change my own fuel filter. or is it best to take it in and have the shop do it. is it pressured?

i had the auto zone do a check. my engine light was on. they said it was too lean. maybe a fuel filter replacement or bad gas. i added a fuel injector cleaner first and got chevron supreme 92 octane gas. to see if that will clean out some crap.
anyone has any ideas please go for it. thanks guys.

 

It is under about 40psi of pressure. There are various ways of draining it off. The one preferred on this forum seems to be to kill the pump with the inertial fuel cutoff and run the engine until it stalls. The shop way is to bleed the pressure off through a fuel pressure gauge which has a hose to safely let the fuel run into a container. If you release the pressure at the fuel rail's test port by hand, you have a chance of getting sprayed with fuel.

Anyway, however you release the fuel pressure, you will need a fuel line disconnect tool. There are two flavors, one is a scissors type metal tool that has two sizes. The other is a set of plastic collars. Both do the same thing, the plastic ones may be easier. There are posts somewhere on this site describing the procedure with pictures.

My main point is that knowing a code doesn't give you enough information to buy parts. All you know so far is that under some condition, your truck ran lean. Among the things that could cause this, in no particular order: vaccum leak, fuel pump, fuel filter, fuel pressure regulator, bad MAF, dirty MAF (on decel), bad O2 sensors. Many of these only cause problems in certain conditions, for instance a vacuum leak doesn't cause problems at high RPM or at high load. A fuel filter will cause problems at high speed and load before it will at idle, etc.

If your truck seems to run OK when under load (no surging or loss of power) it is probably NOT the fuel filter. A rich condition is not urgent, but a lean condition can be. Good luck.

 

It is very doughful that the fuel filter is the problem, but replacing it certainly can't hurt. Drop the 92 octane gas, it won't clean the system any better than 87 will, but it could lower your fuel economy and cause harder starts when cold. If the light comes back on, take it to a reputible shop and have it checked, there are many things than can set a lean code.

 

I think the running lean codes usually tend to point to problems with your O2 sensors...but I dont think changing your fuel filter would be a bad idea if you havent changed it before.

 

I agree. Change it if it hasn't been done. Another way to relieve the pressure is to pull the fuel pump relay. Fuel filter problems usually show up first in performance losses.

 

Check your vacuum line from the pcv valve to the throttle body.There is a rubber boot at the tb that can get cracked or holes in it. Also,your MAF sensor could be dirty,esp. if you are using an aftermarket air filter.

About the fuel filter,it can be changed without having to relieve the fuel pressure.To me,it takes too much time.I can change mine out in 5 minutes or less. Just wear safety glasses and have a rag handy.