Hi everyone, its starting to get cold in Texas! getting in the low 30s at night and my truck wont start! started noticing this issue last year. the truck has 187000 miles on it reg oil/fuel filter changes. the truck wont start without the block heater on for 2 hours and today after reading 300 posts about the issue to no avail i took a look at the heater grid. it seems like its not really heating up when we turn the key and it goes through it cycle. yes the coil is lit for 10-15 secs but today when i actually unbolted that intake part above it and felt it it was just warm? is it time for a new one or something else? thanks!
-Louie

 

If you are plugged in the ECM will not demand much from then grids.

The grids should also not be required for starting at 30, many people don't run them at all. I remove mine in the summer and it starts just fine in the 20's. Cummins advertises them as not needed above 10f.

I would look at other things. Are your injectors still original?

 

yes all stock and i only plug it in when it wont start but the coil light goes on for 15 secs? the grid is definitely trying to heat up it activates at temps below 66

 

It activates when the intake manifold temp is below 66, 2 hours of block heater should have the block around 90-100 in mid 30's. Even in the low teens my intake manifold temps are above 66 with 90 minutes of block heater use.

 

Sometimes the truck won't even start at 50 degrees the gird is not heating

 

I would have the injectors tested

 

Even if the grid is not working this is not your problem.

I would think injectors.

 

The grid doesn't have to work for the truck to start, you have another problem likely fuel related....injectors most likely.