Ok then, the truck runs as it used to. Started this afternoon without glowing it, as before. Has decent power again...or certainly better than it had recently been. Beats me about the idle. All I can figure is it must have something to do with poorly atomized fuel. It wasn't getting any more fuel, just not atomized very well, which explains why I could never seem to set up the other motor properly, with the bad injectors. I think the other motor isn't nearly as bad as I thought. I believe this is the learning curve part. I guess my only excuse is diesel stuff comes to me as an interest without training, just what I read and do. Gee, aren't most hobbies like that?

Which brings me to a question: after opening the old injector, I see the opening pressure can be adjusted very easily, whereas the VW ones were adjusted by shimming the spring (as per the manual), so now I wonder if increasing the opening pressure will help atomization? Has anyone played with this? A fellow at work thinks this is what is done when boosting the HP in a diesel, no doubt with other mods. As I have heard and read of other accounts where guys say they could easily smoke the tires on their diesels (Paul I believe you may know of one fellow I speak of), mine is no where near that, although roasting the tires is not my interest. Clearly, if these claims are accurate, them my truck is really down on power. So anyway, the Isuzu manual mentions starting pressure as 1493 psi. Then on another page it says 1707 psi. And finally on the pump page, it says injection starting pressure is 2133 psi. I guess ya just pick the one you like the most, or something. Whatever.
I'm going to crank the pressure on the old injector tomorrow and see if it sprays properly, and if it does, crank it a bit more and observe.
A simple, reversible adjustment is worth a try in my mind. Especially the reversible part. <img src="/forums/images/graemlins/kewl.gif" alt="" />