I hear this constant hummming noise when I start the car, and when hit the power windows for example, the noise goes lower. In other words, the drain on the battery by using the power windows makes the noise disapate (sp?)...Is that noise the fuel pump?? I can't really tell where it is coming from for sure but it is in the back somewhere. I hope it is not the rear end or tranny...I don't think it is. But.....what do you guys think???fuel pump???thanks......cjf

 

well ... not sure if the noise is only when the engine is on, or if it's just when the car is in motion. i'm pretty sure that it wouldn't be the rear or the tranny if it's affected by an electrical drain, but if you hear it only while the car is in motion, then it could be (if the drain is strong enough to affect the engine's power) ...

i'm assuming you're not running the stock pump, or you wouldn't be thinking it might have something to do with it ...

try to give a little more info ... hopefully someone out there will be able to help you out.

 

You hear it as soon as you start the car. It does not have to be moving. You hear it as soon as you start it up. Like I said, an electrical drain effects it. The noise or the problem is not effecting the car at all. It runs great!. There is just an annoying humming sound that is just ....annoying....When a fuel pump is going , how do you know?. ...and , as far as I know, original pump. I have not taken it out and infact, I am not really sure where it is?..I think it is some where in the vacinity of the fuel filter. Correct?? The pump is the only thing I can think of , that is why I said the pump. But I really have no clue what it is. Nobody else out there has had or has this problem?? Thanks for your help.....cjf

 

well ... i really don't know what it is, but i will say this ...

if it's a stock pump, then you will not hear it (and yeah, it's right by the filter ) ... but, in 11 years and countless Rx-7's, the only time i've ever actually heard a fuel pump make noise is when the stock pump is replaced with something other than an OEM mazda unit. and even if the improbable happened, and it physically worked itself loose, you shouldn't be able to hear it prominently over the engine. if anything, you should hear it mostly when the key is turned to the "on" position, right before you start the engine.

since it's when you start the car, and it's not in motion, i think it's safe to rule out the tranny and rear now.

so .... from what you said, it's a noise coming from the driver's side rear on the car. man, i have no other clues of what it could be ... sorry i can't be of more help , but at least we were able to rule out those things ...

good luck and i hope someone else can shed some light on it for you.

 

is your stereo on when this happens?

 

diabolical1 -
Just wanted to throw this in and not to be a jackass or anything but you can hear my stock fuel pump when the key is in the on postion.

 

hey, I never thought of the stereo. It is an after market stereo (cd -am-fm Jensen) but it was not "on" per se but it is of coure hooked up. I will look into that. It may be coming out of the rear speakers .....huhhhh...will check that , thanks!!!. I will also check the fuel pump to see if it is non-stock... maybe put my ear right in that area when the car is running.......going to check those two things and let ya'all know...if anyone has actually had a similiar problem and "know" what it is, please jump in....thanks....cjf

 

my vote's on fuel pump, i'd almost bet money on it. wanna know for sure? disconnect the fuel pump fuse and turn the key on. if the noise is gone... voila! i've heard the stock fuel pumps from the driver's seat in every rx-7 i've ever owned.

 

I'd say it's the fuel pump as well. The stock pump isn't normally very loud but it can get that way if it's about to **** itself.

 

its rocky as he's getting ready to race your car around picking up pennies with the rear tires.

or it could be poorly shielding ignition wires or some of your noise cancellers missing/not working in your engine bay. if the pump doesn't do the trick listen to the speakers..............

 

i swear to you guys ... i have NEVER heard a stock pump make noise whether the car was on or off ...

but i guess i stand corrected ...
sorry

 

I hear a muffled sound from my stock fuel pump upon turning the ignition key on. (1983 vehicle) I am wondering if this pump is about to give up as I get a miss fire in the engine at all rpm levels. I removed it last night and put 12 vdc to it. It pumps but flow is easily shut of with my finger over the return line. I would believe the 3-4 psi it should generate would require more effort to shut it off.

Let me know if any of you have any thoughts on this.

 

That's because you were dead-heading your pump.

At least it's not making a boinging sound. (get it? hummm vs boing-boing-boing)