Strange Noise In The Backseat?!

[R33Keaton]

Hey guys,

just took my backseat out, parcel shelf and speakers out, to change my suspension.

All went well with the change of shocks and springs but i took the car for a test drive and theres an odd electrical noise coming from somewhere in the backseat... I checked the speakers, it wasnt the problem... And seeing as i didnt muck around with any electrical stuff when changing the rear suspenision, im puzzled to know why theres a static noise present. Its not the stereo as the radio and cds work fine still...

The sound seems to be linked to my acceleration, as when i accelerate it changes noise and gets a little louder. And when i dont have my foot on the accelerator, the noise is still there, but just in a quieter "idle" form...

Does anyone know what this problem may be?

Thanks for any help

[R33Keaton]

possible fuel pump issue? Or is it only loud because i have the backseat out?

Is this normal?

Prior to me doing the suspension, there was no noises heard or noticed at all

[mad082]

if you have the seat out then you will certainly hear the fuel pump louder than with the seat in.

[Carbon 34]

Hey guys,

just took my backseat out, parcel shelf and speakers out, to change my suspension.

All went well with the change of shocks and springs but i took the car for a test drive and theres an odd electrical noise coming from somewhere in the backseat... I checked the speakers, it wasnt the problem... And seeing as i didnt muck around with any electrical stuff when changing the rear suspenision, im puzzled to know why theres a static noise present. Its not the stereo as the radio and cds work fine still...

The sound seems to be linked to my acceleration, as when i accelerate it changes noise and gets a little louder. And when i dont have my foot on the accelerator, the noise is still there, but just in a quieter "idle" form...

Does anyone know what this problem may be?

Thanks for any help

Your amp is picking up the electrical in the rca's

Ground looping it you wont hear it until youngive it some juice

Your fm antenna in the grid is picking up noise

Your fuel pump is dying or struggling to find ground

Your missing sex toy is found??

[R33Keaton]

I think its the fuel pump. I don't have my sub or amp in or anything yet. Just back speakers. I'll try put the back seat back in and see if it hoes away. Could be that the fuel pump can he heard louder with the seat out like mentioned above.

Sex toy? Haha.. nah I'd be sure.to never lose it haha

Thanks gang

[Spurdo]

didn't you say it changes with acceleration.. so would i be correct in assuming what you mean is it will change with RPM? i've had this noise before in a previous r32 it was just some kind of electrical noise coming from the speakers, it would go up and down with the rpm of the engine and turning volume up/down on the stereo had no effect on it. a while ago i read that it may be something to do with having a shitty worn out battery and having ancillary devices (like head units, and in turn, speakers) getting their power not so much from the battery, but having to rely on the flow directly from the alternator, which might explain why the noise changes with RPM?

i'm no auto electrician so could be a complete load of crap but sounded semi-legit to me, as i know my battery at the timewas definitely not in great shape.

i wouldn't think its the fuel pump because im pretty sure they stay at a constant work load? they dont pump more/less as required, thats what the fuel regulator in the engine is for... if you can hear the fuel pump, then it will always make the same noise. nothing will change it's volume, and once you start moving any road noise will usually drown it out

Edited November 16, 2012 by Spurdo

[HotPlates]

Did you work out the issue Keaton?

I have the same noise/symptom in my R33; except I haven't taken out the back seats. Everytime I use the accelerator a whining noise presents itself. After I take my foot off the accelerator, there is a 1-2 second delay until the whining noise disappears.

[ZacZerbst]

Sprudo is quite right with what he is saying. Get your battery tested or even borrow one to test it. Another quick option would be to turn off your sound system and even disconnect any amps if easy to do so and then see if it still makes the noise

[sadr33]

picosong.com/33X8/

Does it sound like this. mic position is about where the steering wheel is. Windows closed.

Edited November 20, 2012 by sadr33

[sadr33]

didn't you say it changes with acceleration.. so would i be correct in assuming what you mean is it will change with RPM? i've had this noise before in a previous r32 it was just some kind of electrical noise coming from the speakers, it would go up and down with the rpm of the engine and turning volume up/down on the stereo had no effect on it. a while ago i read that it may be something to do with having a shitty worn out battery and having ancillary devices (like head units, and in turn, speakers) getting their power not so much from the battery, but having to rely on the flow directly from the alternator, which might explain why the noise changes with RPM?

i'm no auto electrician so could be a complete load of crap but sounded semi-legit to me, as i know my battery at the timewas definitely not in great shape.

i wouldn't think its the fuel pump because im pretty sure they stay at a constant work load? they dont pump more/less as required, thats what the fuel regulator in the engine is for... if you can hear the fuel pump, then it will always make the same noise. nothing will change it's volume, and once you start moving any road noise will usually drown it out

The fuel pump definitelly makes a different noise at the slightest touch of the accrel pedal compared to idle and the fuel pump is obviously working at idle too. So you could say its load based but only a simple 2 stage on off .

Hot plates i know your issue exactly because i have had it. you touch the pedal any ammount and it makes the whiny noise for about 2 seconds the stops. if you keep on holding the accel pedal it will keep going.

The whiny noise doesnt change with rpm its just a whine off whine on deal.

[HotPlates]

picosong.com/33X8/

Does it sound like this. mic position is about where the steering wheel is. Windows closed.

It's hard to tell; but I don't think so. The whine sound in your clip seems to get louder with the rpms. Sounds like a combination of turbo spool & pod filter suction.

The fuel pump definitelly makes a different noise at the slightest touch of the accrel pedal compared to idle and the fuel pump is obviously working at idle too. So you could say its load based but only a simple 2 stage on off .

Hot plates i know your issue exactly because i have had it. you touch the pedal any ammount and it makes the whiny noise for about 2 seconds the stops. if you keep on holding the accel pedal it will keep going.

The whiny noise doesnt change with rpm its just a whine off whine on deal.

From what you described it sounds the same. It's like a constant 'electronic' whine sound that doesn't change in pitch regardless of the revs and stops 2 seconds after the foot off the accelerator. I'm not sure if it is the fuel pump because when you get into the car and turn the key, you can hear the fuel pump activate; and this sound is different to this 'electronic' whine when you touch the accelerator pedal

Did you find out what was the cause?

Edited November 20, 2012 by HotPlates

[HotPlates]

So I just changed my fuel filter (Ryco Z201) and for the moment the 'electronic' sound has disappeared. Fingers crossed this is the solution!

[R33Keaton]

Hey guys, managed to resolve the issue as when I put my backseat in the sound disappeared. I'm assuming it was the fuel pump making the noise. My car is pretty much as good as new, so I didn't think anything major couldve been wrong with it. Alwell, the problems fixed now. Any others who are having trouble similar to this, and your backseat is in, I'm not quite sure what the issue would be???