dead J30 - fuel pump?

[Eswift]

so, I haven't driven the car since last wednesday.

went to start it today, started, but revs never really settled to an idle and it just died.

re-cranked, chugs along at correct RPM with starter, but obviously no combustion.

replaced all plugs about 2 weeks ago, has been running fine since until now.

under-hod check, wiggled connections here and there, checked grounds, battery is now at about 11V after lots of attempted starting.

checked the ecu for trouble codes, self diagnostic : all is well.

fuel lines seem to give quite a bit, possibly no line pressure? should they be quite firm as I would imagine?

fuel level is fine about 1/3 tank remaining.

no smell of gas underhood

tried starting again an hour after the first attempt, same result.

i seem to remember that as soon as i used to switch the ignition to "on", i could hear the fuel pump hum a bit before i started it.

I also recollect that the pump has been louder in the past 4ish months, it was notieceable after the car was on - sounded like a Ford pickup fuel pump - (you know what i mean if you've heard one)

so, the question is - any other diagnostics i should do?

can i replace the pump myself?

could it be the fuel pump relay?anyone have any experience with these pumps going out, their replacement, or cost?

looks like i could get it out without removing the tank, which is a plus.

I was in my 300zx tank once to replace a level sender, and i really would rather not have to deal with the fumes again... (i dont have any way to drain the tank here)

any help?

[IvoryJ30t]

one thing i can think of is get a helper, and have them crank the car while you push the shrader valve under the hood to see if you have fuel pressure. [valve is on fuel rail, or at least should be]

if you have pressure, pull a coil pack and see if you have spark.

[cweberj30t]

Is it getting spark? Could be the pump or the MAF. Seems like the MAF has been the source of problems as of late in colder climates. I would remove it and give it a good cleaning check throttle bodies put back together and see if it changes anything. I'm assuming you made sure you had the right gap on those plugs right?

[cweberj30t]

Fuel pump is around $250 and I think you can get to it if you remove the back seat. Not sure, haven't done it yet.

[DAEDALUS]

Check the pressure with the gauge, or the fuel pump current with an ammeter. *Could* be the relay, but the slow death is a clue, plus the noisier pump. On the Q, a noisy pump is a sign of a quickly worsening condition, and ignoring it can lead to failure of the pump controller, which actually costs more than the pump itself.

[Q451990]

Have someone turn the ignition switch from off to on while you're squeezing the fuel line. If it doesn't swell, you don't have fuel pressure. That was my scientific test when I had a bad fuel pump.

Your assumption is right, it's definatly something you'll feel. You won't be able to squeeze the line closed with your fingers if you have fuel pressure.

Heath

[Eswift]

Fuel pump is around $250 and I think you can get to it if you remove the back seat. Not sure, haven't done it yet.

access to the tank and pump is through the trunk.

ill try the various tests mentioned and we will see where that puts me...

dont think i've seen a shraeder valve anywhere on the engine that i can push, but we'll see.

in any case, thanks for all the helpful hints so far guys!

[NISTECH]

have someone crank the car while you crawl under the back and beat on the tank with the palm of your hand. alot of times when a fuel pump goes dead this will jar it and engauge it. I have done this on a few different cars when they get towed in. It beats pushing it into the shop!!!

[Eswift]

I smacked it good and it didnt even give a whisper...

[NISTECH]

yea its a luck thing even if it did work it would still need replacement but that would have comfirmed your problem. sometimes it works others it wont. but as they said the whine from it was the strong indication of your problem. did you have someone cranking it over when you hit the tank. the pump only runs for a few seconds when you first turn the key on normally. it will start back up during cranking and during a run condition. but will not stay running if it does not see a crank signal.

[Eswift]

so i pulled the fuel pump fuse because I was going to check the filter etc, and just for the fun of it, i cranked it with the fuse completely out. car started, choked, died.

replaced fuse, it started right up, a little hiccup, waited for idle to stabilize.

car has been running fine since (for 2.5 weeks)

any ideas?? (ive got my own, too)

[madmax88]

cool

[slin]

so i pulled the fuel pump fuse because I was going to check the filter etc, and just for the fun of it, i cranked it with the fuse completely out. car started, choked, died.

replaced fuse, it started right up, a little hiccup, waited for idle to stabilize.

car has been running fine since (for 2.5 weeks)

any ideas?? (ive got my own, too)

Where is the fuel pump fuse? I had a similar problem with my G20 and my mechanics ended up to replace the fuel pump, filter, ...etc. After that, it died on me again once so I am kind of lost if it really get fixed.

[Eswift]

in the engine compartment fuse and relay box.