913chase

Hello i'm new to the forum and I am coming here with a rather weird issue. I have a 2006 cummins SLT with 205,500 miles and it's home is in central AZ at 5200 feet with 95 degree summers and 15 degree at it's coldest point winters. The weather lately has been in the mid to low 30's at night and mid 70's during the day with no moisture to be spoke of so the humidity is a nice dry 15-20% The truck has straight 4" exhaust, stock intake with extra holes in the box and a Banks Automind hand held programmer set on the tow/haul mode. I've uninstalled the programmer and it makes no difference

Okay with the back story done here's whats going on, it doesn't start in the mornings unless i use ether (don't worry i let the grid cool down before i spray) I've narrowed it down to a temperature related issue only, i can let the truck sit for 5 days and as long as its above 50 degrees it fires right up no problem. Run down of what I've done to the truck, 2 red top Optima batteries(clean connections) fuel pressure limit valve, fuel pressure sensor, cross over tube inspection and re torque (42ft-lbs) fully operational grid heater, clean fuel filter, no diesel in the oil I've been tracking it for a 1000 miles.

Will start without fail every time if temps are above 50 and it only needs to crank for on average of 3 seconds. In the morning it's been an average of 35 degrees, i will crank the truck in 10-15 second intervals with cranking RPM's of 200. After 4 cycles of cranking i can hear the batteries getting weak so i let the truck sit, spray the tinniest spray of ether i can do in the intake horn and it fires right up. Now the part i'm lost on is after i start it i can let it idle for 10 seconds and shut it off and it will continue to fire up all day no problem even if its still 30 degrees.

So in closing the truck won't start if it sits in the cold over night, has 0 hot starting issues. If you guys need anymore information i will get it to you as soon as i can. Thank you!

Mexstan

Are you sure that the grid heaters are actually getting hot? Have you measured the actual voltage at the grids? Do the grids cycle after it starts and can you see that on the voltmeter?

patdaly

I'm going to move this to the 3rd gen section where more eyes will see it.

I'm not much of a space shuttle guy, but I bet it ends up being something in the programming that doesn't allow it fuel under start conditions under a set temperature.

If you know it is getting fuel, then it could be the fuel isn't of sufficient volatility to fire st the colder temperatures, but I doubt that because of the closeness of the temperature it will not fire at.

StealthDiesel

A hard start issue with a CR Cummins is extremely common.

The grid heaters do not actually help with a cold start. They only help the engine run better after its started.

Most likely your fuel rail pressure is low. Numerous things can cause this from the CP3 pump, loose connecting tubes and worn injectors.
A search on this forum for hard starting will give you tons of info.


BTW, there is a reason that very few Dodge Cummins guys run Banks products. Banks products are not that great and way overpriced.

There are much better ECM programming options for your 2006 Cummins. Including EFI Live..

CRF450R RIDER

what is your cranking fuel and rail pressure?