1993 240

I'm hearing a moaning from the engine compartment. It sound like a power steering pump going bad, but the fluid looks good and when I listen to the pump with a stethoscope, seems OK. What's weird about the moaning is that it seems to correlate more to the amount that the gas pedal being pushed, rather than the amount of steering being done. I have recently cleaned the throttle body, and although this helped some stumbling/stalling problems, it has made no difference with the moaning.

I was going to try and take off the drive belts one at a time, to see if I can isolate it that way, since the mechanics's stethoscope hasn't helped. Otherwise, seems to be working fine, and I'll just attribute the moaning to being 10 years old, and waiting for the thing to get worse, and then it'll find me. But, I'd rather be proactive.

Thanks for your input.

Tom