1998 Mercedes-Benz M-Class - Cranks but won't catch

The battery drains when I connect it. The SUVs Engine won’t turn over. I cranks but doesn’t catch.

A bad crankshaft position sensor can prevent an engine from starting.



I’ve changed the crankshaft position sensor. And it still has not started up. I responds the same way

Does it get spark? Is it getting fuel? Is it getting compression? You need all 3 for it to run.

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you need to give a little more info. what do you mean battery drains?
it cranks but does not catch? do you have any codes? did you have the battery checked and made sure connections are clean and tight? did you check the fuses and relays? do you get spark at the plugs? do you here the fuel pump turn on and are you getting fuel to the engine?

I need to go check All three of those.half the dashboard light shut off right before it stop running.

You may be looking at a bad BCM.


No codes came up when I connected my code reader. I put a new battery in. I cleaned the battery cable connectors I changed one of the battery cables. I changed the streering wheel sensor. I checked all the fuses… I haven’t checked the spark plugs. I haven’t checked the alternator. The fuel injector can be heard when I turn the ignition to 2.

My next stop is a mechanic. I’m a rookie in training

Thank you for sending me that link! That’s what it is!