Really rough idle on cold startup

[patrickc]

fmotorsport410, It will not hurt the truck or block heater to be plugged in all night it will just cost a little more on the electricity bill. Your truck should have a block heater from the factory check in behind the front bumper or the front of the inner fenders from the factory they tie them up out of the way. (hide them) If you still can't find it you can always chase the cord from the engine block.

 

[madkaw]

I'm sure I'll be corrected if I'm incorrect, but I believe the 6.0's sense barometric pressure and outside/inside temp. The computer actually will retard the timing based on these measurements to aid in cold weather starting. Your manual should describe it in more detail.

 

[Tail_Gunner]

FWIW: Last winter, my 7.3 would start really rough with a significant amount of bluish smoke, especially if I didn't have it plugged in.

Well, last summer, I replaced all my glow plugs in conjunction with my new injectors. Afterwards I checked the old glow plugs to see if any were bad, and found 3 of 8 to be dead.

My point is, don't use your block heater to cover up for bad glow plugs. These engines are supposed to start without the block heater down to 0*F. If you are starting rough and the temp is only +20*F to +32*F, you might very well have some glow plug system problems.

 

[RoyBoy]

The latest FICM reflash activates the injectors for approx. 30 sec after shutdown, which pumps the oil from them. There is no cold oil in them at startup to cause "stiction", which is probably what yours is doing. Mine was really bad, got the new flash, a huge improvement.