Usually a cummins will start any temp as long as the fuel isn't gelled without the grid heaters. They are a starting aid not necessities. People in Canada well below freezing don't wait for them and start fine. So your probably wasting time looking into grids.

Try and turn the key on wait for light to go out and repeat 3 times without starting. Maybe it's a weak lift pump.

 

thats what i was thinking weak lift pump. batteries are all good?

 

could also be an injector returning to much fuel and the slow spinning of the engine when oil is cold may not meet rail pressure needed for ecm.

seen it before if it is will get worse to where plugging in wont help

 

I bought this truck used off of someone 4-6 months ago and was told the batteries were both replaced within the last two years. I have not had any other issues related to make me think batteries are weak. Both seem to test fine at advanced auto parts and charge and stay at the 14 mark when truck is running.

How would one go about testing the lift pump to see whether or not it was bad?

Also if it were an injector is there a way to test that or troubleshoot to determine that it may be injector related?

 

use a scanner to see cranking rail pressure

 

i live in a cold climate and went 8 years on original batteries with zero problems. Never plugged in, parked outside, it's cold here! Last year it was hard starting in the fall and by winter woudnt start unless plugged in. checked the batteries and they checked fine but after eight years i thought "no way" and changed them. Fixed the hard start right then and there.

 

Quick and dirty while you are waiting for the injector line blockoff caps to check injector return fuel for above specs. Order miller #9011 2 of them in case you have multiple injector return valves leaking

Q&D> Retorque the connector tubes that feed the injectors, 6 located in the driver side of the head. Might get Injector Lotto Lucky, loose tube that's heat sensitive to sealing.

After the Miller caps are in your hot little hands, test the individual and total injector return fuel per step by step you can find on the forum.
If higher that spec and the injectors are over 100k miles, tits up injectors, replace all with NEW Bosch/Cummins ONLY, NO rebuilts NO Joe Smuck Diesel and Pepsi shop specials, ONLY NEW or you will be doing it again shortly

Or if the injectors are over 100k miles with only inadequate stock fuel filtration, injectors and tubes are rusted and worn out from water/dirt. You can skip the injector tests and put in NEW ONLY.

While you have the injectors out, BE SURE TO run a compression test.

HPCR Cummins will start down to 0d F easily with everything up to snuff without the grid heater and to below -40d F easily with everything up to snuff.
I started mine at -50d F couple winters ago in NWT, no place to plug in the block heater at night.
Wasted your money throwing parts at it.
Grid heater really doesn't lock on for extended duration until it's nut freezing cold, 30d F and lower. Then you think it's going to suck the batteries down the wires into it, draws 200 amps, far more than the puny little alternator puts out. You'll see it on your voltage gauge, don't be scared, just let it do its thing.

Use the block heater until you get the parts in to fix it.

 

what he said ^^^^^ sorry i didnt go into detail was really busy. i suggested a scanner to see if you have to low rail pressure to start then as mentioned you can start capping off each injector intill you find the bad one.

but its best to go ahead and get a new set..

good luck... a good diesel shop should be able to do this test if you cant get a hold of a scanner.

 

Also, CP3 can suck air in from a poorly install canister filter O ring or incorrectly not tightened canister cap that only partially seals. Vacuum caused by low capacity output from the lift pump, failing pump, wiring current limiting, plugged tank pickup, damaged fuel line somewhere between pump and stock fuel filter canister
The CP3 is capable of pulling several inches of vacuum right thru a failing in tank lift pump, not like the old weak nutted VP44 that self destructed quickly from lack of diesel/overheating.

 

Hey, did this truck ever get fixed. My '03 is doing the exact same thing. I ruled out a bunch of stuff including intake air heater. I used an uncoded key tonight to be able to get a long crank to check fuel rail pressure with a scanner. PSI was in excess of 6000. It will drop to 5degrees C tonight. I know it will not start in the morning. I will check fuel pressure at the rail with the scanner in the morning using the proper coded key. When it doesn't start, I will plug it in for about an hour and it will fire right up and I will go to work.
I bought my truck used about 7 years ago and it never failed to start on the first bump. Then this past summer it took about two bumps to start once. At that point I thought something was askew. It has gradually gotten worse, to the point now that I have to plug it in.
I have not ruled out the crank sensor. Scanner will tell me cranking RPMs (or not) in the morning
Can someone tell me at what rail pressure the ECM should activate the injectors?