Cadillac Repair: 93 deville making loud whinning noise, power steering pump, warranty period

Question
i just bought a 1993 sedan deville, 123,000 miles 4.9L it runs great but it is making a loud whinning noise, in park and as i accelerate. It is in sync with gear shifting. when in park it gets louder as i give it gas. It kind of sounds like an electric motor. where is the noise coming from?

Answer
Hi Kyle,

     It makes it tough to tell where the noise is coming from because I can't hear it firsthand. However I do have some suggestions on how to determine where it might be coming from.

     The alternator, power steering pump and transmission all can make whinning noises. I would check the fluid level and adjust as needed for the p/s and trans...adding fluid might make the noise go away. You should be able to tell where the noise is coming from...front or rear of the engine. If from the front then a mechanics stethoscope you can buy from Sears or a 2' piece of rubber hose can be held to your ear and the open end moved around to help tell where the noise is. Also if you are careful a longer flatblade screwdriver can be placed on the alt. and p/s pump while the handle is put on the bone next to the little flap that would cover your earhole. The serpentine belt could also be removed to see if the noise is from the engine, accessories or trans.

     It is not unusual for a transmission that is starting to fail to make a whining noise. If the fluid is darker and brownish or burnt smelling that could point to the trans. Doing a trans flush or service probably won't eliminate the noise most times but it might be worth a try changeing the filter and flushing the fluid.


     If unsure about the noise or want a second opinion then I would suggest taking it to your mechanic. Some used car lots have a 30 day warranty period so you might want to go back to them and see what they will do for you. If you bought it from a private party then you could go back to them and see about getting your money back especially if it turns out to be a trans. noise. Or go ahead and fix it if it turns out to be a p/s pump or alternator.

      Hope that helps and let me know if you need anymore advise. Bill