3406e not happy

Hi Guys,
Haven't posted in a while. I guess thats a good thing. Thanks for the help with earlier 3406e problems. Still read the forum everyday and have gained a lot of insight.
Here's the new situation: I have a two part question..........

Truck had a starting problem last year. I really dont know if it ever was solved. Replaced cam sensor and it seemed to help. We dont drive the truck everyday, maybe 2-3 times a week so it's hard to get a consistent feeling on whats its doing.
Heres what I can tell you- 1. If it sits unused for a while, its a crapshoot if it starts on it's own. It may sit for a week or two, then will fire up on its own. Sometimes it needs a shot of ether then it starts. Sometimes during the day if we shut it off, it does the exact same thing. Once it starts, whether on its own or ether, it runs fine until you shut it off.
2. Tach does not move on cranking. Tach is very lazy while running.
3. Temp runs at 200 or slightly above. It's a dump truck so load runs are varied up hills, down hills, flat roads, sitting at job sites and quarries, etc. When you put some power to it, temp goes up to about 215-220 and takes a long time to come down. Even if I leave fan switch on, it seems to not cool down to below 200, even with no load on flat road. Engine oil temp never goes above 175, ever.
4. After a run, if trucks sits idilng for a few minutes, it starts to puff out blueish smoke and starts to run a little rough. It cleans up on its own, or if you start to move for a few hundred feet or so, then goes away.
No general power loss or poor running during the day(other than above).
All of the symptoms happen all the time in no specific order. ECM or something else?

Second part. I think I'm just going to invest in software or Cat ET. Any opinions on the best all around package ? Is it better to buy a scan tool with preloaded software or something to use on a laptop. No looking to spend a fortune as I'm not a repair shop, but I have two Cat trucks and looking to add a third. If I had the software, it would help in the above matter, I hope.
As usual, Thank You in advance. George

 

Hi,
Thanks for the replys. If the head was cracked, wouldnt it smoke most or all of the time. The smoke/rough running does not happen every time I stop. I've been trying to keep track of how many times it happens. Also, when its just sitting at idle, it doesnt smoke at all. Its very odd ! I started to keep track of coolant use and it so far is using none. Thats why I wonder if is the ecm going nuts and making the guages and other systems act funny.

Thanks, George