Yesterday I went to start my car and it wouldnt go. It turns over fast, and will continue to turn over even after I release the key. It wont stop turning over until I turn the key back. I thought it was a faulty FOB, but I tried both and they both did the same thing. I took the batteries out of the FOB and tried to start it and it did the exact same thing. Is this a security issue? Is there a way to reset the security?

If I leave it for a half hour it will usually start again fine.

 

this is normal on a benz with a smart key. almost all benzes do this, its called tipstart.
so when starting the car all you have to do is turn the ignition key briefly and it will continue to start the car even if you let go of the key. this is normal!!
the no starting could be a crank sensor. but it is not related to the car continuing to crank when releasing the key.again that is normal.

 

problem seems to be completely intermittent. And the longer I drive it, the better chance of it not starting. But if I let it sit for 20 minutes, it starts again fine.
Could it be the fuel pump?
After I get it going again, the engine light always stays on for 10 minutes or so, Maybe I'll just go get it scanned and save myself the headache