wmoguy, when this was going on did your truck start harder than usual or did it start the same. I ask this because my truck is doing the same exact thing you are describing to a T. It started a couple months back with some rough idling since then it has progressed to a crazy amount of white smoke during start up along with rough idleing. it gets a little better when warm but is always rough at idle. When driving down the road and i let off the throttle out comes the white smoke. I checked all the normal things then determined with amount of mileage (175000) it was the IP pump. I am actually ready to replace it. But you have me second guessing myself. i thought it could be air intrusion but my truck can sit for 5hrs or three days and it still starts right up, on first glow cycle, I assumed that if I had air intrusion I would have issues starting it, or keeping it running during start up. it other than the fog of white smoke during start up, it starts just fine. Any Thoughs ?
Mine recently seemed to have more challenging starts. Prior to these issues, it always started at the flick of the key. Rewind about another month ago, my rear tank stopped working. Basically it would run on it for a very short time, then it billowed grey'ish smoke and sputtered horribly until it finally died. I had figured I either had an issue w/ fuel pickup lines or the FSV valve but just didn't have the time to get in there and do the job so I just started using only the front tank. Fast fwd to now, I began noticing the same issues on the front tank in terms of rough idles and smoke.
I too was basically convinced I had killed my new IP and/or injectors. I do run ALOT of WMO blends and had hoped to get more than 7 months from an IP, but had pretty much determined it must be an IP issue.
I did the clear lines pre fuel filter after installing my electric fuel pump, and low and behold I had tiny air bubbles in the lines. After this past weekend where I completely gutted the fuel lines in this thing including the return line after the injector return lines; I have no more problems. This morning it was chilly, not cold (it was 34 degrees) and it cranked right over in less than 2 seconds of starting (it was not plugged in either) New injector caps and return lines were put on this pickup last fall when I had the top end of the engine rebuilt.
Mine has 238k miles on it, and I'm almost 100% certain it's got the original FSV on it, and I'm certain the tanks have never been dropped to do the fuel pickup line modification. My best guesstimate is the issue mine had, and likely yours based on your comments, is it's either the FSV or your pickup lines giving you fits. In my particular situation, I'm about 99.9% sure I don't have rusty hardlines w/ leaks, as this pickup is 100% rust free.
From my limited understanding of how our DB2 pumps work, and just taking in what Ken @ DPS was telling me about them; air running thru your injection pump long term is not a healthy thing at all. I don't remember all the potential risks, just that he did tell me it can actually destroy a pump. At the least, enough air in the pump while running hard will make the timing do all kinds of crazy things. THis all makes sense to me, because prior to my "fix" when I went out to flog my pickup after adding a BUNCH of Dieselkleen, the thing surged @ 80mph very badly. I also had varying degrees of diesel "clatter" depending on the day. More grey'ish smoke gave me more diesel clatter
I will say this, no matter what you do, absolutely put an electric fuel pump on your IDI. I've read many a folk state they liked the difference, and I'm hear to sing that same tune as well. I see minimal benefit at all of the mechanical pump and dont think I'll ever be going back to one.
