Unidentified scraping sound


My car (2004 Nissan Sentra, manual, around 70k miles) makes a slight scraping sound from around the area behind the steering column. The noise only appears after the car has been driven for a while. Just reaching the normal operating temperature of the engine is not enough. When I’m stopped and the engine is idle, the noise disappears. As soon as I touch the gas pedal, it appears. The noise is not affected by turning the steering wheel, brakes, gear, electronics, engine rpm, AC settings or anything else I can find. The scraping sound is non-rhytmic and can’t be heard over the engine sound under the hood, so it’s very difficult to localize (it can be heard clearly inside the car). The mechanics I tried didn’t find anything since the car has to be driven for a while, but the noise eventually appears every single time I drive more than 10 miles. I think I’ve reached the limit of my car knowledge, so any suggestions for what this might be would be greatly appreciated. Thanks!

Bring it to the dealer. They will know of any free maintenance that can be done to correct it. It could even be coming from the transmission.