Ok, I've seen this question asked a couple of times, but not with\nenough info to fully describe it so it could be answered.\n\nI have an 89 240 DL. A couple days ago it started making a strange\nwhining noise when running at 50 mph and above. It is not a grinding\nnoise like a bearing or brake pad. It is not the hum from a fuel pump\nissue. It is not the squeal of a belt slipping. It is more like an\nelectric whine that comes from the front of the passenger side. Upon\nhitting 50 mph it starts like a small electric motor spinning up to\nhigh rpms until it gets to a steady high pitched whine. Then if I let\noff the gas, it sounds like it is spinning down. My wife compares it\nto the sound of a tiny jet landing when decelerating. When I try\nrevving the engine, while parked, to an equivalent rmp I do not get\nthe sound. I'm sure it's not the fuel pumps because I've just\nreplaced both and am very familiar with the pump noise. I'm also\nfamiliar with belt squeals, brakes grinding and bearing noise and\nthat's not the type of noise I'm hearing.\n\nThis is stumping me so any help will be appreciated.