tjakacki

Parked my 97 E420 outside for a few days here in Madison, WI and didn't drive this weekend. All of a sudden it is running rough and CEL comes up. I pulled out my trusty Code Reader from Harbor Freight Tools and got the code P0115 Engine Coolant Temp Circuit Malfunction. Any Suggestions??

A few months ago I had some cylinder misfires and changed ignition coil on either cyliner 7 or 8 and has run fine until now, could these be related??

FlatlineEF9

noticed any coolant leaks lately? usually that happens when your water pump seal is leaking.

Ricco

Check out my solo thread:

https://mbworld.org/forums/e-class-w...20-issues.html

E-420

Mine had a similar problem, don't recall if it was the same code, but my thermostat was bad, was opening early, and when below freezing on the highway it would throw codes because engine temp wouldn't come up. (wouldn't reach much above 60C, at 20F outside)