fuel pump question

[akaslick15]

how do you know if the fuel pump is bad or not working properly i hear the noise that the pump make whenever i start the car but i been getting a loss of power problem and really bad gas mileage like 120-130 miles per tank bad!! i had changed the plugs wires fuel filter cleaned the maf twice new air filter yet still having this problem the only thing i havent touched is the fuel pump and o2 sensors really need help here thanks guys

 

[akaslick15]

anybodyyy???

 

[OnyxCobra]

I don't think a bad fuel pump could cause bad gas mileage, usually when the pump goes the car doesn't start. I'd say of the two the O2 sensors are much more likely.

 

[akaslick15]

man bro your like the only guy on this forum that helps me out wtf is wrong with everybody else thanks alot OnyxCobra

go ahead and lock this post or delete it cause wtf is the point....

 

[Musturd]

Yea I'd agree with onyx that it very well could be o2 sensors

 

[5.0kid]

go to oreilly or advance auto and have them test for codes. thats always a good place to start.

 

[akaslick15]

ill start from there

 

[MustangChris]

fuel pumps rarely "go bad" like a mechanical device. these are electric units. They are either broken, or working.

if you think its the fuel pump, i suggest cleaning your MAF. Unplug your battery for 5 minutes and plug it back in. If that doesnt help, and you still think its your pump:

then, i would go to the trunk, dig out the wires that run to the pump and check them with a meter.

Fill the car 1/2 full of gas (the pumps are fuel cooled, be sure to try and always stay at least 1/2 full) with gas from a "different" station. if you go to the same station every time for your gas, and they got a bad batch, you could be filling your car with bad gas for months... (dont fill the car all of the way up, as you may have to drop the tank.)

after this, i would test your fuel pressure at the rails. this is a simple process.

if all this goes okay, let us know.
and we'll go from there.

a 302 expert will have to chime in to tell you what kind of numbers you should expect on the meter, what fuel pressure you should see at the rail, etc. etc.

 

[akaslick15]

@ mustanchris thank u bro ill keep u updated ..the only thing thats holding me back is the time cause of work

 

[MustangChris]

i hear that.

if dropping the tank is the final solution, dont sweat it...

you'll need a socket, an extention, a ratchet, a flat head + hammer, and those magical a/c hose disconnect tools.

drop the 3 bolts holding the tank, disconnect the fuel lines (hardest part,) hit the fuel hat laterally with the flat head and hammer (to spin the hat) and lift the hat straight up.
replace fuel pump(s), install is reverse of removal.

we dropped my tank to install my pumps.
then it went back in.
then dropped it to run lines.
then back in.
then to install filler tube.
then back in.
now its back out to drill for the battery-relocation box. :-(

oh, if you do drop it, order a new filler tube gasket now. replace it whenever you can because it goes bad every few years...

seriously, to me, it sounds like a dirty MAF, but we shall see.

 

[rz5.0]

Get a gauge and check you fuel pressure. Sometimes fuel pumps dont put out enough and do need to get replaced.

 

[F1atlander]

as RZ said check fuel pressure. ive had to replace many fuel pumps because they were weak but still worked. i still dont see it costing you fuel mileage but it a problem to check of the list.

 

[OnyxCobra]

any time dude. And I'm not sure they can check for codes if the CEL isn't on.



and bad gas for months? I see gas trucks at stations like once a week at least usually.

 

[rz5.0]

You can get codes at anytime not all of them give a cel

 

[akaslick15]

ok so my brother had told me start the car and pull the plug off for the maf and if its driving better maf is no good or if the car starts choking and dies the maf is ok so i pulled the plug and the car died like in 3 seconds so i know its not the maf.. ill check the fuel pressure and start from there where should the correct pressure be at and how do i check it?

 

[MustangChris]

lol. i dont think thats the way to check your MAF.

just go buy a $2.00 can of MAF cleaner and clean it...


I can only give advice on 4.6 fuel pressure info. ive never done it on a 302....

 

[akaslick15]

ino how to clean it ..very easy but i cleaned twice in the past 2 months so thats not really helping... i feel like its bad o2 sensors but this week ima check for any hiddin codes and just clean the o2 sensors and see if they make a difference

 

[MustangChris]

just saying unplugging it and if your car farts blue smoke and then replugging it in and it it farts white smoke "voodoo" mechanics is questionable... i wouldnt rule it out so fast because of voodoo... thats all im trying to say...

 

[evilcw311]

who do voodoo??

 

[akaslick15]

lmaooo its funny cuz my car does farts here and there