insame1

Hi All,

Bought a glk350 and it has a very slow crank. It always starts but very slowly. I replaced the battery and recently left the car sitting for 10 days. came back and it started like it normally does (slowly) but it started. I am guess since that is the case the battery is not loosing power. I am guessing the starter is getting old but dont want to swap it on a theory. Any other things i should be looking at?

John CC

First, have the battery tested for capacity. Then, verify you do not have a big voltage drop between the battery (+) and the starter or the battery (-) and the engine block. If that doesn't expose anything, you can do a draw test on the starter motor. If it's bad it'll draw excess current. If it doesn't draw a lot, and still cranks slowly, repeat the voltage drop tests.

chassis

When did you most recently replace the battery?

Mmr1

Yes you need the battery properly tested, If you have a volt meter testing voltage now and test it with someone cranking the motor, the amount of voltage drop will be a good idea of the issue. What brand , capacity and type of battery did you put in.

insame1

less than 6 months ago

Mmr1

I had a name brand battery go bad in one month . Most auto parts stores will give it a full test for free.