I have a 2003 Dmax 2500. This past winter I had some starting issues. If I would let set like a day when it was cold it would not start until the outside temp would warm up. So I took it into the shop and the first shop said there was an issue with the glow plug controller. So we contacted GM and found out there was a recall on the glow plugs. Had them changed and it still done it. So I took it to another shop and they told me that I had a bad battery cable and that it was not getting enough voltage to turn the motor over fast enough, which I thought was weird. So while it was there I had them to check my injectors and found out that i had 4 bad ones. So I had all of them replaced. By the time I got it back the weather had warmed up and I am still not sure if the problem was fixed and was just wondering if anyone had any input on this. I also had my cam sensor go out about 2 months ago and had it changed too.

 

bad battery cables can cause slow start up. you can do a voltage drop test while cranking and see