Cold starts

[Donman]

New to owning a diesel and I have a 2001 7.3, was wondering what color and how much smoke is normal for a cold start?

[JK23112]

For a truck of that vintage, seeing one "puff" of blue smoke when you start it in the morning should be okay. Anything beyond that, you need to keep an eye on it.

You also need to consider how many miles you have on it, how well it has been treated and whether or not all of the glow plugs are in tip-top shape.

[Donman]

It has almost 170k. It used to not smoke on startup at all but
Last few weeks usually smokes quite a bit on startup, usually blue/grayish mix! Has been pretty well maintained I think. I bought it from the second owner who had it for 10years, and seemed pretty on top of all maintenance has records for all services since almost new. Just got a little worried about the rolling smoke for about 2 minutes.

[Tj Krawler]

Have you changed where you get fuel recently? Using any additives? Does it smell like unburnt fuel? Does it run rough when you start it? Have you checked the GPR?

This winter my truck was smoking a lot on cold starts and had more blue smoke under 50-60* I wanted to see. Changed the additive I was using and now I hardly have any smoke at 25*. This is with a mildly weak GPR.

[Donman]

You know it does seem like it maybe where I get fuel. The pumps have been running real slow and I don't think they get used a lot? It does smell like I unburnt fuel. I haven't checked the GPR, and I use diesel klean every now and again.