runs rough till it warms up

[tephrite]

Ihave a 97 4wd stock except for a kn air filter with 260000 miles.
when its cold out the truck will intermittently idle rough with a loss of power and will have a check engine light that will not throw out any codes
once the truck is warm it will not run rough anymore and the check engine light goes off. if i shut the engine off it will start and idle no problem until it goes into closed loop and then the check engine light goes on and rough idle starts again

[SCUFFY828]

this is a diesel engine , you confused me with the closed loop part, diesel doesnt have that , that goes with gas engine and oxygen sensors

[tephrite]

i was told when you first start the truck the obd2 will put it into a kind of safe mode then put the different sensors online this is what seems to be happening because it will idle fine for about 5-10 seconds then it will light up the check engine light and run rough

[SCUFFY828]

to an extent but doesnt haved alot of effect on way vehicle runs , with a 97 model 7.3 with that mileage there could be several things causing concern, injetor wiring , ipr , icp pressures , really need to start ,with basics ,is oil in good shape and full, do you have a way to pull codes , need to know what codes are in pcm, the pcm does go thru a check once engine is running ,if it does see something light will come on

[tephrite]

the oil is fine including in the hpop resevoir im thinking its probrobly not a pinched wire because it will run fine for 5-10 sec if i shut it off and restart it
i tried retrieving codes from the pcm but i didnt get any

[SCUFFY828]

if the light is coming on at all you should have a code , what scanner are you using

[tephrite]

i have a junk scanner so i when to auto zone to see if they could get the codes but it also came up blank

[SCUFFY828]

need to run more diag , with a good scanner , like injector buzz test just to make sure no injector electrical issues , without any codes to work with its gonna be hard to diagnose ,look at all wirng close , maybe look at all your injector wiring going into vale cover , 94 - 97 are bad for melting the injector wiring ,sometimes if its bad enough you can see it on the outside , pins damaged etc.

[cchase]

i have the same problem, excpet once its warm, it completly goes away.

[areed1234@]

put cetane boost additive in.
Reduces misfiring during warm-up https://www.amsoil.com/storefront/acb.aspx