have a problem with my 2004 E500 sedan. drive to a store, when I come out of the store my car won't start. All power works, but won't start. Unable to be jumped off. After sitting for a few hours then it starts. Had it checked and they can't find out what the problem
is

 

I have had my battery tested and they said it was fine. they checked the alternator and said it was fine. I drive my care everyday. I could have just driven it to the store and whenI come out of the store it won't start

 

Starter?

 

Why do you figure it could be the starter

 

well if you had your battery tested and is OK so is the alternator.
Starter is the only thing that left ... from what i see.
plus idk about other than 550s but it was a somewhat common issues on v8s. Had mine replaced by the dealer.

 

It could be HEAT SOAK. I had an '04 E500 4Matic, but never experienced heat soak with the starter. If you Google that term, you will see what it is and the symptoms are exactly as you have described. Most modern cars, though are designed to avoid that age old problem of overheating the starter. In any event, I agree with Mr. Belarus27 and it is your starter causing your problem.

 

I would seriously look at the Crank Position Sensor (CPS), which you can only test by replacing it. Only use a true Bosch part, not an aftermarket.
They tend to fail when warm, then work again when they cool off. Common to all MB cars that use them.

Had this happen on my wife's W212 Bluetec, as she was driving down the road, and when I came to rescue her everything worked fine, as it had cooled off.
Replaced the CPS, and everything is fine again.

Let us know what you find.

 

can that cause longer cranking time?

 

Engine needs to turn over before it can start.
So what exactly is it?

 

I should have asked...is your engine cranking over, but not starting?
Or is not even clicking and the starter is not turning?

Option 1 could be a CPS. With bad CPS it will crank, but not fire. CPS is used to trigger ignition by telling ECU when it is TDC.
Option 2 is likely something else.

 

This shouldn't be in the W212 section...