Wtf!!

[jmeti000]

here we go again!! 76 280z L28 efi... it keeps getting this really loud buzzing sound from the fuel pump. it started about a month ago...it was making a slight buzzing noise and then just basically flooded itself and crapped out on me on the road...i waited about 15 min and it started up again just fine, but blew out gobs of black smoke and smelled really rich. so i drove it to the auto parts store and replaced the fuel pump (cuz thats were all the noise was comin from). worked great for about 2 weeks and did the same thing again..noise starts out very slight and gets raging loud over a couple of days and then starts to flood itself again. i finally bent down and felt around while it was pitchin a fit one day and the vibration isnt actually coming from the pump...its stongest were the lil fuel damper diaphram is linked to the pump..can these actually go bad cuz i thought it was just a simple diaphram that smoothed out the fuel flow.. im on my third fuel pump and its started it again...ive changed the mass air flow...again, and it quit doing it for a couple days, then started again... ive also had new injectores, fuel regulator, filter,fuel hoses, air flow regulator, and cleaned the throttlebody...any ideas??

[hls30.com]

I would Drop and clean the tank, it has probably been loading the pumps up with junk and that is why they are getting noisy.

Will

[Ed]

Install a filter between your tank and the pump.

[webdawg1]

Have your tank sent off. (Moyer fuel tank renu) http://www.gas-tank.com/

Might not cost as much as you think...Recently had mine done and it looks really good inside after they got done with it...

webdawg1

[jmeti000]

oh ya.. i forgot to say that...i did put a filter between the tank and the pump before i installed the latest one 3 days ago.. it still made the noise right away at first...then i realized that the hose was kinked so i had to fix that problem...then it was perfect till today... it started makin the noise very slightly and intermitently...after i turned it off and it sat for about 10 min then it was fine. but tomarrow will be another story im sure. gee, wonder what im gonna be doing over thanksgiving.....

[hls30.com]

The filter is probably clogged-drop the tank! The problem you had only proves the problem is with the fuel intake-your tank is probably fUll of little stuf that uLtimately cloggs the pump(now the filter), and big stuff that blocks the pickup-thats why it runs again after sitting a while. It sounds to me like you will keep having these problems untill you drop the tank and get the junk out of it! I think you would be more effective addressing the problem rather than the symptoms. Dropping and cleaning the tank should get and keep you out from under the car and back into the drivers seat...

Will

[BRE-240Z]

Have you drained the tank? It would be interesting to know what the fuel looked like. I would guess that there are some big flakes of rust/gunk/goop that are blocking the pickup tube inside the tank.

[zbane]

"it's stongest were the lil fuel damper diaphram is linked to the pump..can these actually go bad cuz i thought it was just a simple diaphram that smoothed out the fuel flow.. "

Methinks you've answered your own question...

Like anything, I imagine that this can and does go bad. I think it equally possible for them to get all gunked up. I agree with everyone who has posted that the culprit lies in the tank, but now that you've got the filter between tank and pump, that should stop the problem from re-occurring, or at least make it more definable. Since the problem hasn't stopped, and you noticed agitation in the damper, I'd go ahead and pull the damper and clean it out. Who know's what you'll find in there.

If you were to pull that off for inspection/cleaning, it might be wise to use this opportunity to back wash the fuel line to get out any other accumulated crud. That's just a thought off the top of my head, but I figure if you're there already, you might as well.

[=Enigma=]

Not to be redundant here......but it sounds like you should drop the tank.

[mholmes]

Dropping and cleaning the tank on all old Z cars should be something that is to be expected. I have learned this the hard way that the engines, systems are very finicky and require clean tanks. For less than $200 you should go ahead and have it done cause you will have to eventually anyway.

[biddljj]

I didn't want to drop the tank in my 240..... When I finally got around to it it was easier than I thought...

[BRE-240Z]

I haven't dropped mine yet, either. The previous owner told me that he had boiled out the tank and that it was in good shape, but that wouldn't be the first whopper he's told me.....

I did drain the gas and it looked good, but you never can be too careful.

So, I went ahead and bought a clean tank on eBay, and it's just waiting in the garage for the party to start....