Cold Start Idle Rough Batt Light?

[SDLooksgood]

06 6.0 48k

This am registered 34 degrees on my dash. I started the truck after letting the glowplugs warmup apprx a minute longer than normal. The truck did fire right up but almost immediatly began to run rough. Not the shaking you out of your seat rough but rough. I also noticed that my battery light flickered on and off.

2 miles down the road and the truck was still running rough but no battery light

5 miles down the road and at a red light, the truck continued to idle rough but then I witnessed the transition to where it smoothed out and began running normal. Truck was approx 3/4 warm per temp gauge.

Batteries where replaced Sept of 07.

Any idea what this could be?

Thanks for any replies.

[Goose350]

Idle rough is somewhat normal. Have you had the cold weather reflash done to the truck? Do you just crank up your truck and then start to drive it?

Edit: and I have no clue about the batt light

[SDLooksgood]

Thanks for the quick response Goose350.

I had my truck flashed mid last year. My understanding was that the Inductive Heat Flash was already a part of the flash code. Perhaps not. How can I confirm?

Anything below 60 degrees I tend to wait out the glowplug light indicator by an additional 15 to 30 or so seconds. Doesn't both me much more to wait. This AM I did just that by waiting 30 more seconds before firing the truck up.

I do have an easy time gauge to go by. It takes my audio systems head unit 30 seconds to spin up and begin playing it's last tack.

[Clay Henry]

get your batts tested, sounds like they are toast.

[SDLooksgood]

Originally Posted by CHenry

get your batts tested, sounds like they are toast.

I guess my next step. Thanks CHenry.

[Clay Henry]

Originally Posted by SDLooksgood

I guess my next step. Thanks CHenry.

Have your alternator tested as well, either one of those things could cause the light to come on.

[SDLooksgood]

Update.

Firstly, No, I have not had the batteries or alt tested yet. That will be this weekend unless I am forced to otherwise but...

This AM was 30 degrees outside. The only thing I changed in my routine was I enabled the OSD via the dash button combination to monitor the voltage during start and while running.

While I sat with the key on I had my Lights, Nav/DVD player, and butt warmer on. The OSD registered 11.4 volts.

As I was turning over the motot, 9.6 volts was seen.

The truck fired right up and it skipped initially but cleaned it's self up really quick. 11.4 volts was seen.

It had that normal tightness that a cold engine does but it was not any where near as choppy as yesterday.

I get 100 yards down the road and the voltage has risen to 13 volts. I did notice a big spike too, glow plugs dropped off maybe?

2 miles down the road and I am at that red light again. Voltage has risen to 13.6-7 volts.

As I cruise down the road at 70 for the next 15 miles, the voltage consistently stayed at the 13.9-14.1 mark. With a high of 14.1.

I started running the heater at about mile 5 too and did not see a change.

The only thing I did was topped off my Duralast gold batteries with distilled water. Water level was not low per say but low enough that I felt they needed to be topped off.

The battery light did not come on at all??

The only other thing I can think of about this issue is on Monday, it was the first time I started the truck as it sat all weekend in 35 degree weather.

Any input guys/gals?

[SDLooksgood]

FYI...Batteries tested and alternator. Everything is good.

Seems I'll be waiting it out if there really was a problem.