Fixed FICM Still Cold start Issue! Help, Thanks

[rizzamike]

Need help, searched threads cant seem to find the answer.
Fixed FICM 2 weeks ago, works now, Been But having issues starting, don't believe FICM related there is absolutely NO stiction now when it starts. Colder weather to -8 it starts fine but colder lately -12 or colder it wont start up! I try to start the truck and it almost starts then re cycle the glow plugs and same, almost but wont stay running. The only success I have in the cold is over cranking the starter. I know it is hard on the starter but it's the only thing that works, keep the starter turning as the truck seems to start and it will. Now I notice the lights on the dash flicker when I turn the starter over, It never did that before. also a slower cranking speed on the second starting attempt. Starts fine when the engine is warm or warmer weather.
New battery's 2 weeks ago, oil change 2 weeks ago 5w-40 synthetic, fuel filters 2 weeks ago
Could it be alternator? fuel pump? or something else? Thanks for any help!

[capcalvin]

-12 is pretty cold. Are you using any kind of fuel additive with anti-gel? How did you fix your FICM? Did you get it replaced or resolder it?

[rizzamike]

I had it professionally resolder the FICM, Usually use fuel additive but I might miss the odd tank of fuel but there was in the last few tanks.

[capcalvin]

I would still have the voltage output checked while cranking cold. Resoldering does'nt always work. Even if done professionally. Bench tested might be fine but when its actually installed in the truck and -12 deg. it could act totally different. Just saying, I would not rule out FICM totally untill tested in vehicle, cold, cranking voltage. Do you have any codes stored? You may have to take it to someone and have them hook it up to a computer and check everything while cranking cold. These engines are practicallly impossible to troubleshoot without a computer.

[rizzamike]

Voltage was checked, It produces all the right numbers, It was bad but the Resoldering fixed it now it runs great when I start it, It ran real rough before. No codes present

[rizzamike]

Changed the alternator, Works great, and even my fuel milage went up on the gadge as soon as I put it in. Thanks