bphnn

I just recently purchased a 03 E500 from a family friend for what i thought was a "steal."

The car has 72k miles, I cant seem to figure out why when first starting out, the engine starts excessively loud, I know it wouldn't be silent but for a MB I wouldnt expect this much noise. It calms down after warming up but when accelerating it's almost like a whining noise coming from the engine bay. Could it be a fan maybe? I tried looking up similar post but with no luck on a fix. Thought I should ask some experts before I take it to the stealership after only owning the car for 2 weeks.

xr650rguy

My guess would be the belt tensioner pully.

Second guess would be your power steering pump (check the fluid level/quality?)

jimbo1mcm

Could be an idler pullery. The old time mechanics would put a wooden dowl to their ears and place the other end near the possible source with the engine running. Wear track shoes in case you get thrown pretty far from the car.

mcleantmw

Do you have the AC on in the auto mode...........if so, the engine will rev up with a loud noise to quickly help cool the inside of your vehicle.

ruffrob

Many including myself have seen this problem,so refill your reservoir

yoram611

hi ,

I have the same problem , I hear the whining noise as if it is coming out from the AC area , the dealer thinks its from the AC compressor`s pulley , in my car it is not possible to replace only the pulley , I dont want to replace the whole compressor just because of the whining noise.

my car is a 2003 E320 .

m4coyote

I have the same whining noise on my 2005 E500. The power steering fluid was OK, but I flushed, and refilled it with Pentosin CHF11S fluid anyway. The idler pulley bearing was quite worn, so I replaced that as well. All of this was to no avail, because the noise was still there.

I then removed the serpentine belt, checked for play in the AC compressor pulley, and bingo, there it was, the AC compressor pulley bearing was worn, and it had quite a lot of lateral movement. I have been spraying the threaded end of the compressor shaft with PB Blaster penetrating oil for a while now. I hope that when the time comes to remove the pulley, it will unthread without twisting off the end of the compressor main shaft. I find this quite ridiculous for a vehicle with only 42K miles.

vettdvr

Now wait just a minute here,, I resemble that remark, but I quit using the dowel and now I use PVC pipe.

Our 2003 E500 has been doing this since new. The idle pulley was failing at 75,000 miles when I replaced the belt. The new pulley was only about $20 and an easy fix. I doubt you would ever hear the idle pulley as the bearing is so small and if it fails the pulley will stop, belt will melt the pulley and fly off the engine.

I gave up 5 years ago trying to find where the noise comes from on start up. It goes away after running to a lower level.

m4coyote

Ours is also louder at initial start up, but the whining sound is quite obvious after the engine is fully warm. There has been Technical Service Bulletin issued about the AC pulley and its associated whine.

Vettdvr, how do you like your vette? I have a Machine Silver 2005 MN6 C6, and it has been very trouble free compared to our E500.