Mystery grinding sound when start car

When I start my car, a 2002 Mercedes C230, (past warranty) it makes a whining, grinding sound that stops after about ten minutes while driving. IF I start the car soon after the sound is gone. However, if I wait an hour before starting the car again, the sound is there again.

-One mechanic said it might be the steering wheel pump but that first by adding special oil that works on Mercedes , ($150) it might fix it,

-Second mechanic said it was probably the steering wheel pump and that he would have to take out the antifreeze compartment to thereby fix both.

-third mechanic said the sound is from etiher the steering wheel pump which would cost $650 he would get from Mercedes to replace plus labor or might be from a tiny hole in something like a hose

-Mercedes said would cost $150 to diagnose the problem and $250 for the pump (if that is truly the problem) plus labor.

-AAA diagnostic center said could diagnose the problem wiht one hour inspection for $65 and if steering pump , I oculd buy the pump from Mercedes and bring it in to them to put it in.

Suggestions?

The first thing I would do is start the car and asses where the noise is coming from. If it is making that much noise it should not be too hard.

First of all, who were these mechanics?

Secondly, how did these different mechanics come by their diagnoses? Did they open the hood and look around, or were these things done over the phone?

The consensus seems to be that there’s a problem with the power steering pump, but we need to know how that consensus came about. You need to give us more information if you can.

You can’t, can you? It’s OK. We realize there are people who know nothing about they workings of their cars. Actually, you are the majority.

I suggest you take this car to a MB dealer and let them fix it. Yes, it will cost a bit more, but they will do the job correctly, and that’s what matters.

The Mercedes dealer is the place for you. They won’t say “might be,” and they won’t try to sell you “special oil,” which is worthless. Take your car to the Mercedes Benz shop and pay whatever they ask. It will be less expensive, in the long run, than letting someone who doesn’t know what he or she is doing try to fix your car.

First suggestion is to replace the starter which has a faulty solinoid that is forcing the started gear to stay engaged until you hit a bump that knocks it free.

That might be a solution, but I would suggest that the OP confirm that the starter solenoid is really defective before throwing expensive parts at the problem.