I have a code of P0672 which the autozone description shows #2 cylinder glow plug, faulty connection, or glow plug controller connection. Any ideas which specific error P0672 is?
Thanks, Nick

 

does the glow plug light come on after car has started/while driving?

 

The glow plug light and the check engine light come on after start, a few seconds later the glow plug light goes out and check engine stays on continuously.

 

Does it start okay or does it crank a few times before starting in the mornings?

 

It starts fine, all the time. I am in Florida where it is warm (hot) actually.

 

It seems very likely that it is the glow plug module, they are a common failure on the GL. I just replaced mine with similar symptoms. Easy to install and cost about £120.00

https://mbworld.org/forums/m-class-w...cel-p0672.html

 

My 2008 E320 bluetec is showing these similar start problems now at 120k miles. The car would start instantly before, even at -30 to -40 C (Minnesota and Ontario winter) previously. But recently, even at reasonably warm temperatures (10-20 C) it would need multiple cranks, show the ignition and check engine error lights. Codes shown have been p0671, p0673 and p0670, at different instances. But they all go away and the car runs great the rest of the day, often for a few days, until the problem shows again. Should I just change the glow plug module or also all the glow plugs? I don't want to be stranded in the winter. Thank you very much for suggestions. Also, are these easy DIYs?

 

Since it gave the controller code, I would certainly try that first.