I have a 2001 ML320 w/50k. It uses coolant but appeared to be leaking. I found one hose that needed tightning and that fixed one of the puddles. However when looking under the oil cap I found a yellow gooey substance indicating water and/or coolent mixing with the oil. Is there a moisure trap under the cap or is this an indication of a leaking head gasket or cracked engine block? It does not blow white smoke.

Also, recently the keys came out of sync with the doors. I followed the directions to fix this but they have failed. Now about four days later the parking lights are flashing every 5 minutes and the interior lights come on and the car unlocks. It is not possible to lock the car. Anyone with any ideas would be appreciated. Thanks.

 

I need the same information. I have a 2002 ML320. I went to the dealership and they added some coolant (MB of course) When I drive my coolant level indicator comes on but later goes off. Is this a problem consistant with the ML? Do you have to use the MB coolant? thanks in advance.