white smoke bad mpg

[Jimbo33]

Hi, I knew I have seen it as i searched for it through these forums. I have an 08 f250 crew cab 6.4L with 16k. I noticed that when i'm dead stopped and hit the gas, not all the time but sometimes it blows white smoke. Also, When I was sitting and idling for no more then 5 min, I was actually watching my AVG MPG dropping by .1 and probably drop almost .7 total in 5 min. What does this mean? Ideas? The truck is bone stock. If I go to dealership what do I say? I'm new to the 6.4 as my last diesel was a 7.3.

Thanks
James

[elongate]

Normal. I get a little white smoke from a stop while in regen. I don't know if it's moisture or what but it lasts only a few seconds and only in regen.

And your mpg will drop while idling because you are using fuel and going 0 mph. It's simple math. You burn 1/2 a gollan of fuel while idling for a while, divide it into the number of miles driven and you get sucky milage.

[Jimbo33]

Well I know when idling it would go down, I just didn't think it would drop so quick. Well I'm still bringing it to the dealership next monday because the a/c isn't really cold, so they are going to look at that.

[Fly5150]

It depends how long ago you reset the avg on the info center. If you've only gone a short distance after you reset the avg, it will drop super fast. But, if you've got a few hundred miles on the reset, and it drops that fast, you might have problem.
Matt