Yeah its not the grid heaters cutting on an off. It hasnt been cold enough here for them to cut on. I still beleive Im sucking air through my fuel line from the tank to the airdog. What do yall think????

 

I had air being pulled in On the suction side and had a fairly significant power loss but idle was fine.

 

Hey dock did you notice a drop in fuel mileage too when u had air being pulled in?? The power feels good maybe alittle low not sure but my fuel mileage has seemed to fall for some reason.

 

i had the samething happen on my 99 dodge cummins milage went down alot i changed my TPS and fixed my surge and milage went back up alot got it from timbo on the interned for 165 with shipping you could try that

 

Yeah Ive done replaced my tps. After I reset the valve lash to .10 an .20 it doesnt seem to idle quite as rough but the rpm gauge still bounces.

 

If it were sucking air, the idle surge would be there all the time, and not just when warmed up. That's just common sense.

Time to look for a different solution to your problem.

Did this surging just seem to come out of nowhere one day, or was it caused by some change(s) that you may have recently made to the truck - such as repairs, or performance upgrades?

I'd check your fuel pressure and flow from the lift pump to the injection pump as a starting point.
Don't care how new your lift pump might be, because you just never know.

Do you have stock fuel injectors, or have you changed them to something larger? Larger injectors can sometimes lead to strange rpm fluctuations if fuel delivery isn't sufficient to get them to atomize the fuel charge properly.

Is the truck low on power at all? Check to make sure all of your intercooler clamps are tight and that there are no leaks in any of the plumbing/boots, etc. (You can spray them down with ether or carb cleaner to see if there are any leaks - which would lead to a brief increase in RPM's.)

Does your truck have an aftermarket power programer installed? They seem to create problems as they age. Try removing it and see if your problems go away. You can always hook it back up later.

 

1st guesses....clogged up filter or trash in injector or pump

 

I have a 2002 cummins that I have replaced the entire fuel system airdog 150 lift pump, bd diesel 100hp over vp44 dynamite 150hp injectors. I replace it all because the lift pump went out and took out the injection pump so I replace it all. I am running a quadzilla adrenaline v2 pulse on it. The truck runs great as long as the engine has some kind of a load on it. When it is brought up from an idle it surges or hunts terribly. I have eliminated the injectors I pop tested them and I isolated the quadzilla. I also pulled the injection pump back of and made sure the key was in the gear correctly. It seems like I have tried everything and nothing helps. There are no fault codes in the ecm. If anyone has any ideas it will help a lot l.