well I have a small problem that I can not figure out..

When it gets cold (40 degrees or colder) I plug my truck in on a timer, so that it is getting power for about 2 to 2.5 hrs before I go to work.

if I plug the truck in at night the grid heater will not cycle.. the "wait to start" light will only come on for about 2 secs like in the summer, and the grid heaters wil not make any noise ( not working)

but if I do not plug the truck in, like when I am getting off work the grid heater will cycle for 30 secs or so with the "wait to start" like staying on the entire time. ( they will make noise )

anyone have any idea why?

I am pretty sure this is not correct but I could be wrong..

Thanks in advance

 

The grid heater only comes one if the intake temp is cold enough. With the block heater plugged in, it warms this sensor up enough that the grid doesn't need to come on.

It's normal. My truck does the same, as do the 12 Dodge trucks we had at work when I lived in Alaska.


Also I wouldn't worry about plugging in your truck until it gets colder than 20*. That is the guideline the USAF gives us for our diesel trucks, so I figured it'd be fine to do the same to my truck as well.

 

Sounds about normal to me. The reason the grids are not cycling is because the block heater has managed to warm the engine up enough that the air temp sitting in the intake on the head is at least 60*F.

To give you another example, I got in around midnight last night and left at 5 this morning. When I went out to start the truck, mind you it has not been plugged in and its 10* out, the grids did not cycle, there was enough heat to keep the intake just warm enough.

 

Ok I was not sure which was correct..

now to add a small twist to it..

when plugged in, I get a ton of white smoke when cold , like last night 15 degrees outside and it smoke white for 10 mins

but when not plugged in and grid heaters cycle I get smoke for about 5 secs then all gone?

any ideas?

 

Its probably due to the grids not being cycled during the warm up. Thats the reason they cycle at first when the engine is first started cold, to clean up the white smoke a little bit.

 

I do the same and get the same results. Only difference is I do it at much colder temps than 40*.

At 40* I'm likley to still be wearing shorts outside and not even thinking of plugging in.

 

I've noticed the same pattern with my truck, in really cold weather if its been plugd in all night the grid heaters will not kick on initially, but once she startes huffing in the cold air and fuel they start cycling right up...
the light comes on but with no squeal, and once the engine starts, my battery gauge indicates that they are activated pretty much right away....there is, probably a 5 second interval before the heaters actually start to heat, though, and there will be white smoke until then
i think the ksb also takes a few seconds to change temperature as well, being right next to the block....but mine is manually activated...
i would just check both the switches with a test light to make sure everything's right during a cold morning start-up..advancing the pump timing helped a lot with unplug cold starts, as did stanadyne cold and 2-stroke in the tank