read every cold start post, no success. PLEASE HELP!

[superdub01]

first, the problem: for the FIRST START of the day the truck will crank fine but will not fire, unless the block heater is plugged in for at least two hours. (regardless of the temperature. it was 60 degrees today) if i try to start it without being plugged in, even cycling the glow plugs multiple times, during cranking, it will fire a little, then die, then fire a little, then die. almost like a gas engine way out of timing. i have gotten lucky a few times and it eventually started, but ran extremely rough (like on 5 cylinders and no power) until i drove and applied 3/4 to full throttle. then it would spontaneously fire all cylinders and run great. for the rest of the day all startups are normal, power is normal, smoke is normal. it has wait to start light, oil pressure, and the tac moves while cranking.

truck has a new GPR and new glow plugs. oil level is fine, however i havent checked the HPOP level because i dont know how to. while the valve covers were off, i cycled the glow plugs and verified that they were all glowing and they all passed the resistance checks.

i'm totally stumped. thanks in advance fellas

 

[Dogman]

What oil do you have in it the summer stuff. 15/40. If it's really cold the oil will be to thick and the injectors wont fire the motor right untill it get warmed up. Also check your batt. amps. need to test them by them self. Could have a batt going bad.

 

[egregg57]

Check your FICM voltage. You should have 48 volts. Low voltage will cause these symptoms.

Also IPR ensure the screen is not blocked or damaged.

HPOP low oil pressure / crank / no start condition is most commom after the engine has been heated up and is commonly caused by a failed STC fitting or dummy plugs.

Dogman is right about oil. I use 5w oil year round, Rotella T-6.

Do you have the ability to read codes?

 

[RoyBoy]

Check your FICM voltage. You should have 48 volts. Low voltage will cause these symptoms.

Also IPR ensure the screen is not blocked or damaged.

HPOP low oil pressure / crank / no start condition is most commom after the engine has been heated up and is commonly caused by a failed STC fitting or dummy plugs.

Dogman is right about oil. I use 5w oil year round, Rotella T-6.

Do you have the ability to read codes?

Looks like we're talking about an '01 7.3L... not a 6.0L

Still sounds like batteries/ ground, etc. or glow plug system. Did you check your GP harnesses?
When you are trying to cold start does the exhaust blow white smoke (fuel)?

 

[egregg57]

My apologies! Missed the 7.3!

 

[JLDickmon]

how did you ground the glow plugs when you did your valve cover off check?

 

[superdub01]

i held each one against the head and verified that they glow red. did them one by one. i like the idea of going to 5w-30 syn. that kinda makes sense because with a few hours plugged in that may just be enough to warm, and essentially thin the oil enough to start. also because if i dont plug it in it cranks extremely slowly.

 

[DaveBen]

5w 30 is for gasoline engines. At least I have NOT seen or read about 5w 30 diesel oil. 5w 40 or 15w 40 is diesel oil.

Dave

 

[iracemine]

both batteries are dead. Try driving to a parts store and then getting them individually tested. Id bet they are just slowly dieing.

 

[superdub01]

5w 30 is for gasoline engines. At least I have NOT seen or read about 5w 30 diesel oil. 5w 40 or 15w 40 is diesel oil.

Dave

ya, your absolutely right. i just wasnt paying attention while i was typing. thanks though!