My 1997 S500V will not start. Battery was replaced 1 year ago. Electric power to all interior accessories still work and the power seems fine. When I turn the key, I can hear the starter turning very strong, but the engine will not run. I checked the fuses in the engine compartment and trunk. All looked fine, even the fuel pump 30amp fuse is ok. With the key is position 2, I can hear a faint buzzing sound from the engine. The car was last driven 2 days ago. It only has 15k miles on the odo.

What might be the problem?

What and where should I look at first?

Thanks in advance.

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Mark
97 S500
91 535iA