6.7 Diesel Ideas?

[jimborokz]

I was told by a very knowledgable deisel guy that once the glow plug light goes out to leave the key on and wait another 10 seconds or so as the heater stays on after the light goes out. I haven't had a cold morning since to try the theory out.

[xrated]

Originally Posted by jimborokz

I was told by a very knowledgable deisel guy that once the glow plug light goes out to leave the key on and wait another 10 seconds or so as the heater stays on after the light goes out. I haven't had a cold morning since to try the theory out.

That theory would be pretty easy to check out if you have an amprobe for AC voltage. Sequence would be:
1. Cold truck with the engine heater plugged in
2. Place amprobe on circuit going to the truck engine block heater
3. Have someone turn the key switch on and verify that the light is on for the heater.
4. Other person looking at the current draw on the circuit.
5. As soon as the light goes out, that person lets the other person know it's out
6. Watch and see if the current drops off as soon as the light goes out or if it continues to pull the same amount of current for several seconds or longer.

Continued current after the light goes out proves that it is true. If the current goes down as soon as the light goes out....theory false.

Another thing to keep in mind, the older Ford diesels (2010 and older), the light stays on for several seconds before going out. On the 2011 and later, with the new 6.7L diesel engine, the light is only on for less than a second or so, in most instances. The new motor has completely different glow plugs that heat almost instantly.