I drive a '99 toyota corolla that has 78,000 miles. When I take my foot of the gas after accelerating at higher speeds, I hear some sort of humming noice that I have never heard before. It almost sounds like the car is having a difficult time coasting. I brought it into a local gas station and the mechanic said he didnt hear anything. Other have been in my car and have commented on the noise. What could the problem be?
Automatic or standard? If standard it could be a heat shield on the exhaust side of the engine. If auto look for a loose heat shield on the tranny side. The catalytic converter also has a heat shield that often loosens a bolt producing the same noise. Bang around on the the heat shields and see if you can find the noise. Sometimes they warp with heat and a little hammer modulation will fix the proble. Good Luck