OK, here is the scenario.

About a month ago, I pulled my trans and had it rebuilt with goerend internals and VB. Took about a month to get it back in and running. I had about 3/4 of a tank or so that I filled up before the truck sat waiting for the trans. So the fuel sat for about a month.

Now, after a hard pull, the engine will idle rough. It's only happened twice, but it feels almost like I have air in the injectors lines or it has a miss. It will idle like that and then once I get going driving, it will clear up after 5 seconds or so.

What could it be? Just bad fuel, or maybe some water in my fuel? I only have 1/4 tank left, so I will be getting new stuff soon. Maybe I do have air in my lines? Maybe a bad fuel filter? Any help is appreciated!

 

Are you still using the stock lift pump?

 

Piston pumped.

 

Do you have a fuel pressure gauge?

 

Nope, no gauge. It sure did run a lot better after the piston pump install, but maybe I am even sucking that one dry?

 

It's possible, but not likely. It would be interesting to see what the pressure is when it's running funky, though.

 

Yeah. The fuel filter has been on there since I got it, so I'm gonna toss a new one on tomorrow. My other diesel buds are betting that its the filter. If it still idles rough with new fuel and a new filter, I will have to toss a gauge on it.

 

What do you mean,(after a hard pull) If you are speaking of a fast, hard pull, then innediately idals rough for just a couple of seconds, It may just be non burned fuel burning, If i quickly let off the gas when at full throttle, with the h20/meth on, i will get the same thing, Youe rpms will drop quicker than the boost, therefore allowing alot of fuel quickly.
Peter.

 

Mine does the low rough idle thing after pulling for several hours nonstop. I figure it is weak return springs in the injection pump.

Andy

 

When I say rough idle, it sounds like it's running on 3 or 4 cyls. It will be after a hard WOT pull, unloaded, getting up to 40 PSI of boost. I have to toss the trans in neutral at a stop or it feels like it'll stall. When I start moving again, it is noticeable for a few seconds, but then feels like it clears up after 5 seconds or so. This never happened before I put the new trans in. I don't understand why this has only happened twice, when I've done countless WOT pulls since I got the new trans in?

I got new fuel in it yesterday, drove 100 miles so far with no probs. I guess I will see what happens.

 

Put in a new fuel filter and new diesel and it happened again. I must be sucking in air somewhere?

 

my truck will do the same thing

 

About a month ago, I pulled my trans and had it rebuilt with goerend internals and VB. Took about a month to get it back in and running. I had about 3/4 of a tank or so that I filled up before the truck sat waiting for the trans. [U(So the fuel sat for about a month.)[/U]



sorry if this question is really dumb, but if your fuel just sits in the fuel tank for a couple of months can it go bad?? hope not since i have two 30 gallon tanks of fuel on my truck and only one is half empty and the other is still full. im still in the process of swapping the 95 12v into my truck so its just sitting.

 

fuel can go bad sitting. going bad in a month.......a doubt it.

If there was water in the fuel and then it got below freezing for a week. the water would turn to ice around the tank screen and caused the truck to starve out of fuel!!!

Fuel additives for the winter will help this problem out a lot!

If your going to pack fuel that you don't us vary often keep it full!

a low tank will draw in moister that will condense into water and sit in the bottom of your tank! the longer the tank sit the bigger the problem gets!

 

is the idle possibly just too low? after a long hard pull mine will seem to idle a little lower... so if the idle is low to start and then it drops a little more, these things will shake you up if the idle is too low, especially with the tranny pulling on it.