Monaro VXR fuzzy noise from boot

[V8Monaro]

Hi

I have a Monaro VXR 6.0 with the small boot. I was playing around with my speakers the other day trying to fit some new subs. The subs I bought do not fit so at the moment I have 2 big holes in the rear shelf where the factory subs go.

I have noticed a fuzzing, interference type noise coming from in the boot. I thought it was from the rear speakers as that is exactly the sort of noise it is. But on further investigation it is coming from inside the boot around the fuel tank.

Is this the fuel pump, do they sound like a speaker fuzzing? Or something else? I'm guessing it's always been there and I've just noticed because I have no 2 big holes going straight through to the boot at the moment. It's definitely not the speakers though even though it sounds like it! It's not loud just making sure it's nothing to worry about.

Anyone heard this before?

Karl

Edited by V8Monaro on Thursday 21st August 16:38

Edited by V8Monaro on Thursday 21st August 17:03

[SturdyHSV]

The fuel pump is a sort of 'on demand' jobby I believe, so it won't be on all the time.

It's not a return fuel system, so once the system is pressurised (quick blast of the pump at ignition), it's then only activated as and when the fuel rail pressure drops due to fuel being used and thus requires more pumping.

What I'm getting at, is if you turn the ignition on but don't crank the car, you should briefly hear the fuel pump, then it'll stop.

Someone correct me if I'm way off of course...

[KMud]

Is it just when you're moving? Tyre roar?

[V8Monaro]

It is when the engine is running, when the engine is off it is not there. Both when you are still and moving, does not increase with the revs it is just always there.

[Tattooboy]

Have you tried turning the radio off?

Maybe the rear speakers are getting interference from the amp as there are no sub speakers fitted?

Perhaps pull the fuse on the amp or turn it down, see if that makes any difference.

[V8Monaro]

I will try mucking about with the amp later. I have actually had no subs fitted for ages I just have a sub in the boot, but the holes for the sub have always been covered with sound deadening. I have just removed the sound deadening because I was attempting to fit 8" subs in to the holes, which don't fit so I have to get different ones! But I have noticed the noise since uncovering the holes.

[Tattooboy]

V8Monaro said:

I will try mucking about with the amp later. I have actually had no subs fitted for ages I just have a sub in the boot, but the holes for the sub have always been covered with sound deadening. I have just removed the sound deadening because I was attempting to fit 8" subs in to the holes, which don't fit so I have to get different ones! But I have noticed the noise since uncovering the holes.

Ferret on here fitted bigger subs in his CV8, he just made up some spacers out of wood and done a rather good job.

They don't have to be that neat as you won't see them, might save you mucking about changing the subs you have! Just an idea

Good luck with the noise hunt, that would drive me crazy as well !!

[V8Monaro]

I was actually planning to use the original plastic things the factory subs were in to fit the 8" ones. I have cut them like you see on the following thread, and I was going to silicon them in.

http://www.ls1gto.com/forums/showthread.php?t=40581&highlight=rear+deck

Unfortunately the Kickers I bought to do this are too big so I need to find some 8" subs with smaller dimensions that work in free air applications, any recommendations would be great.

Anyway back to the problem, I have had a good look and this is not the rear speakers, it is coming from around the fuel tank. I took a video with my phone actually in the boot, so nothing to look at but you can hear the noise. This is me starting the ignition, then starting the engine, then turning the engine off. Hopefully you can hear the fuzzing and faint whine. I cannot think of anything else it could be other then fuel pump, I just did not think it should be this loud!



Any advice would be great, is it the fuel pump?

Edited by V8Monaro on Sunday 24th August 18:37

[V8Monaro]

Can anyone tell what the noise is from that? I appreciate it's a boring video but you can hear it.

[ARAF]

I can't hear it, but my computer is shyte.

Have you tried it with the ignition on position 2, but the engine not running? That should tell you is it is a running circuit, or interference from the engine.

[V8Monaro]

Yes i do that in the video. I get the noise for a few seconds then it stops when I turn the key to position 2. As soon as I start the engine it comes back and stays. You can tell this in the video if you listen carefully.

[ARAF]

V8Monaro said:

Yes i do that in the video. I get the noise for a few seconds then it stops when I turn the key to position 2. As soon as I start the engine it comes back and stays. You can tell this in the video if you listen carefully.

In that case, I would say it is the fuel pump. Whilst it does shut down after it has primed the injection system, my experience with fuel pumps is that they will always run, once fuel is being used (the engine running).

[V8Monaro]

Ok I guess it's always been there then. Must just be able to hear it with the lack of anything in the rear shelf holes. It is fairly loud!

[snowwolf]

Only noise I can hear is the fuel pump for a few seconds

[Xpuffin]

Fuel pump.