help for high pitch noise

volvovera · Post by **volvovera** » 31 Jan 2011, 13:17

Could any one give me some suggestion to diagnose this high pitch noise issue please?
The noise coming from the rear end whenever I start the car. The noise is not loud and does not change when the car is under acceleration and at idle.
With a kind former suggestion from this forum, I had my car checked in a dealership. The mechanic only opened the fuel filler door and put his ear against fuel filler cap and then told me that the noise does not come from fuel pump. He said it was an exhaust noise which is normal.
My question is that whether the fuel pump noise can be so easily excluded without any other check?

Post by **jblackburn** » 31 Jan 2011, 17:31

Do you hear the noise if you flip the key to position II without starting the engine?

volvovera · Post by **volvovera** » 31 Jan 2011, 17:52

When I turned the key to the position II, there is no high pitch noise.

Also I tried to put my ear against the gas cap after I started the engine and opened the fuel filler door, the high pitch noise does not come from inside fuel tank.

FCPEURO · Post by **FCPEURO** » 31 Jan 2011, 18:01

Try putting your ear to the back seat and see if you hear it coming from there. It sounds like a fuel pump to me also.

volvovera · Post by **volvovera** » 03 Feb 2011, 15:06

Thank you for your tips FCPGroton.
As you suggestied, I put my ear against the right side rear seat, and can not hear any noise
Then I put my ear against the part which is leg area under the right side rear seat, also can not hear any noise (sorry for this pooor description)
This time I opened the gas cap, and I can hear a tiny high pitch noise by which means the sound is not as loud as I can hear around the car.