M103/W124 Coolant Sensor on, but coolant tank is okay, cylinder missing below 1200RPM
 

Hello,

Okay first issue is that my engine seems to be running on 5 cylinders upon startup with a cold engine. It remains for a while unless I rev to at least 1200 RPM.

When the engine is warm it is not as common, but still occurs.

Runs fantastic above 1200 RPMs...

The other issue is that my low coolant light occasionally comes on. The tank is at the correct level. (right at the area where the top and bottom plastic molds of the tank fold into each other)

Please advise,
Thanks

Coolant lever sensor gets corroded over time and will give false readings. You can clean the terminal contacts where it connects to the tank, but that will only work for a little while.

Best to just get a new sensor...the part is inexpensive and it's quick and easy to replace at home.

The other issue sounds like an intake leak somewhere, but I'm guessing...