bought an 06 SS/SC last week, and from the day i test drove it and almost every day i drive it, I hear this humming or on/off sequence of humming coming from what I believe is the fuel pump. I don't have any CEL or noticeable problems in the car, but I don't want to be charged for a mechanic looking around for an hour. Is this a thing? or what else could it be?

 

If it has an aftermarket fuel pump (i.e. Walbro) they are louder than stock but you can't really hear it with the car running. Turn the key to on but don't start it. The fuel pump will prime and see if that's the noise you are talking about.

 

I didn't hear it when i turned the key, but I did when I turned the key after a drive to the store. it wasn't loud on the way there, but I heard it as I parked at home with the car still on.

does this sound normal? I would never think it has a custom pump, as the car is bone stock even down to the intake. but then again I don't know the previous owner

 

I would think you would have heard it both times. I'm not sure how long it takes for the system to bleed back off (10 minutes maybe) so I don't know how long it had been sitting when you did it the first time.

My car is bone stock, minus the air box mod, but I changed the pump for a walbro because it would sputter sometimes on start up if I didn't let it fully prime. Hasn't done it since I swapped it out.

If you only hear the humming sound when driving maybe it's a wheel bearing??? You could jack the rear up and spin the wheels to see if it makes a growling noise.

 

I hear it after I stop so I doubt its the wheel bearing. how long did yours take to prime or whatever?

 

Yeah if it does it while stopped then it's definitely not a wheel bearing.

It primes for 3 or 4 seconds when you turn the key to on (not starting).

Maybe post a video of what your problem is.

 

alright got a vid of the humming after I parked the car.


I hear the fuel pump prime on startup, but its a much lower pitch and lasts maybe 2 seconds.

 

So the car is running in the vid? I really don't know what that is. It's weird that it changes tone so much. The only thing that I can think of that's "running" in the back with the car running would be the fuel pump. I wonder if you hooked up a fuel pressure gauge if it would fluctuate with the tone changes. If so I would say it's your fuel pump and something is wrong with it.

 

ok I could try to find a pressure gauge to test it.

If that's not the problem I'll post back here to try to find something else