Recently bought an 04 CLK55 amg with 8,500 mi. for $28K. Incl new tires & battery. It looks newer than new! BUT, the engine would whine loudly on startop from cold , to fade away after c. 4 mins. NOT a low mile $85,000 sound at all. Local (Toledo, OH) MB dealer replaced power strg. pump bearings to fix ($900) but whine was still there! Next, the same dealer replaced some belts and pulleys ($550 - a price break since the original problem had not been fixed!). The second "fix" kept the car off the road for THREE WEEKS with no response to two messages to the service mgr. I picked the car up today and it sounded O.K. (perhaps it was warmed up?) but when I started the car from cold just now the whine is back! After the first misdiagnosis I had the service mgr. plus his top tech LISTEN with me on a cold startup so we would all agree on what needed fixing (that awful whining noise). So now I'm out $1,450 and I've still got that freaking whine to suffer through. Any ideas on (1) how to deal with the MB dealership. (After two ignored phone calls and other signals I strongly. suspect the service mgr. is avoiding me), and (2) what's causing that damned WHINING NOISE?

Probably "secondary air pump", it's one of the most screaming device when the car cold,,

did you check that..?





ZAYED,,

I would do the research and find an independent mechanic who will spend the time to diagnose the problem before throwing parts randomly at the car while praying " that'll fix it I'm sure". Just my. 02. Good luck.

I have same issue at startup, I changed the belt, belt tensioner, idler and AC pulley. I still have the whine but have learned to ignore it.

Mine whines on cold start up, but I don't think its that bad. I'm used to it. I just figured its normal for the engine.
Maybe take a vid of the noise so we can hear if its any louder or worse than what we are experiencing.

Might be the fan clutch,

Just a hunch, when the engine is turned off hot the clutch is engaged, when starting cold it is still engaged until the thermo element on the front un-locks it.

Have a friend start the car while you inspect under the hood, It might get us closer.

All that Jazz, Gator

This sounds like to me like the classic Mercedes-Benz V8 whine. They all do it and it's normal. Mine has been whining for the past 2.5 years (since purchased) on cold start. Shouldn't be an issue. However, like Stiggs mentioned, take a video and we can all tell you whether or not it's the normal whine or something else. I'm 99% sure you are okay.

You owned a benz before? As others have pointed out it seems like Mercedes of this era have that characteristic whine on startup. My 02 clk55 has it, my mothers 2006 ml500 has it, her old ml320 had it, my fathers old s320 had it, and all other Benzes that I seem to encounter or drive have it, although I haven't been around enough of the new new cars to know if it's still got that signature whine. All I know is if I had never owned a Mercedes or had prior experience with them the sound would worry me as well! Again as others have stated try to post a video with clear sound so that we may help ease your worries. Also great find!

Also another tip! Try to avoid stealerships, do some research and you could find there's a very good, reputable independent mechanic in your area with people that truly know what they're doing and take pride in it. Plus you won't be charged the ungodly price per hour for labor. But that's just my experience with Mercedes dealers, I suppose they can't all be bad.

Both my 430 and 55 do it. Secondary air pump... COMPLETELY normal! Every Mercedes that I've driven has done it, and it's completely normal... Heck, even the Chrysler Crossfire (slk320) does it. I'd stop throwing parts at it especially since, if it goes away after it warms up for a minute, you're fine... It's similar to the delayed shifting when it's cold. Old 5.7 TPI Chevy engines had "Cold Start Injectors" for this same reason. It's to assist in the cold weather starting and running of the vehicle.