Engine/Transmission (1994 - 1998) No power, well, sometimes no power...

[MatthewPark]

Today my truck started acting a bit odd. Once it warmed up a bit, I floored it, but it felt like a stock truck. EGTs in a no load 4th gear pull barely reached 700, they usually get to 900-1000 or so. Boost was also low, only saw about 15 pounds, as opposed to the normal 30+. It wasn't rolling any smoke, either.



I drove it around some more and found that occasionally it would act normal, roll the smoke, break the tires loose, boost back up over 30 and EGTs climbing fast. Sometimes it would start out like a stock truck in a 3rd or 4th gear pull, but then it would instantly come alive and make all the boost, power, EGTs and smoke that it normally does.



I think it's safe to assume that for whatever reason, it isn't getting full fuel all the time. I have a #5 plate slid all the way forward, and when I put it in 10K ago, the governor arm was hitting the nose at the bottom of the plate perfectly. The only thing I can think of here is that for some reason, it isn't hitting the plate correctly anymore, and the lever is suddenly popping over the nose, and then it gives me all the fuel. Can the governor lever come out of adjustment on it's own like that? Like I said, it's only happened today, and it's happening consistenly. It was perfect last night. I haven't been into the pump in 10K miles.

 

[Joe G.]

Check to see if your AFC hose is cracked. Either that or the AFC is sticking.

 

[MatthewPark]

The afc hose may be the culprit. I can feel an abnormality in it right where it kinda rubs on a some wires.



I'm going to try to fix this and go from there, thanks!

 

[MatthewPark]

I took a boost line off a parts Cummins we have sitting here, and it didn't change anything. Actually, after I did this, my truck would not give full fuel at all. It was 100% turd burglar all of the time.



After that, I took the plate out of my truck and took it for a spin. Now, I could get it to roll a lot of smoke and pull like it should, but maybe only 30% of the time. Most of the time, it would still be slow as hell, no smoke, no EGTS over 700, no boost over 10 pounds.



Then I put it back to the way it was. I have the #5 plate full forward, no wastegate, and it runs like it should. I can't get the truck to reproduce the gutlessness it had this morning. The AFC wasn't stuck, and everything works fine.



I don't get it.

 

[DCTECH]

Check your fuel shut off solenoid linkage. Remove solenoid and see if

plunger will pull out. If it does or has lots of up and down play when energized

replace it. I had one truck doing same thing and drove me nuts to find it. When had no power, I left running and seen if I could lift solenoid plunger up higher and moved about 3/4 of and inch. It let enough fuel in to start but no power and if hit bump in road would loose power.