Quick back story, I bought this truck with 260k miles on it about 2 years ago. I've been deployed much of that time so I havent put many miles on it. The wife has used it a bit while I was gone.

When returning home about a year ago, it had all the standard symptoms of the PMD failure (drive normal then acted like someone switched off the ignition). I ordered the pmd from pensacola diesel and some glow plugs from them. Installed and relocated the PMD to the front bumper and it seemed to fix all the problems. I then left again a couple months later.

While I was gone, the wife had problems getting it to start (maybe 1.5k on the new pmd). She took it in and they replaced the starter but that didnt help the issue. They replaced the glow plugs and changed all the fluids while it was in.

The starting problems happen on the first start of the day. It will be hard to get it to turn over, it may light off but will then idle low and stutter for about 5-20 seconds until finally the idle gets over 1k and then it will smooth out and idle normally at about 700rpm. During the rough idle it will be pouring out white smoke from the exhaust.

Once it smooths out, it runs fine. You can turn it off, it will restart no problem. If it sits for more than about 6 hours or so, the same problem happens at start.

I took it to the mechanic (not a diesel specialist, cant find one here). He couldnt figure it out and he called the GM dealer who said it would likely need the injection pump replaced along with the PMD.

I'm having a hard time thinking its the IP or PMD since it only gives issues on start. My thoughts are maybe something with the glow plugs. I'm new to diesels so I'm not sure how to go about troubleshooting this. Anyone have any insight or advice? Thanks for the help.

 

the white smoke means that your truck isnt burning hot enough, thus making white smoke. and if it does this only about every six hours, it sounds like a problem where it gets cold, then doesnt want to start.

when was the last time you changed injectors?
how long does the glow plug light stay on?
getting any codes?

 

how long does wait to start light stay on it maybe bad glow plug relay are you getting codes also cts on the T-stat house witch tell the computer what engine temps are and then puter tells Glow plug relay how lone still on for