My truck (2004 dually) when at idle seems to be having trouble. Sounding different ....engine sounds like it cycles or something....gets louder gets softer louder and softer ...and so on....only at idle or when you take foot off pedal. This past winter when it got below zero it would have trouble starting and make a knocking noise when I would start it unless it was plugged in. I do not have any smoke but I do have oil leakin from underneath the valve cover. When I drive it I do notice that it does not have as much power as before. Has anyone had this same experience?

 

04 or 04.5? have you checked to see if its making oil? (pull the dip stick and check oil level and smell if there is fuel in the oil)

 

yea yea! I fixed it...it had been making surge noise so I thought it was the throttle relay...but it turned out not to be....as I digging around for my manual I found a bottle of fuel injector cleaner and put that in the tank along with some other stuff and the engine when from sounding terrible to wonderful. No more surge noise. Stuck injector unstuck! Took it our for a spin and its running good, like it use to. Thanks for your help! No fuel in oil I did check that already.

 

so i didnt fix it after all! the problem has been dragging on and on! as of late i replaced the fuel injection pump and the lift pump and still nada! AND get this my truck has less than 200, 000 miles. UGH sick sick to death of dealing with it.

 

This sounds like grid heaters cycling on and off, the change in sound from the engine is from the sudden draw on the electrical system when the grid heaters kick on. hard staring when its that cold also sounds normal without being plugged in.

Do you see excess oil coming out of the breather top that runs down on drivers side from top of valve cover? If you pop the oil fill cap while its running does it seem pressurized? Could be that your just a seeping valve cover seal....

otherwise feeling like it has less power is not an easy symptom to diagnose...if you still suspect injectors i would take it to a shop with a scan tool and see the %contribution from each injector easiest way to tell if one is not firing without pulling them. Otherwise with that kind of mileage you might want to send out injectors to get bench tested or just replace them all. I've had much problems with my truck at only 90kmiles with 2mic fuel filtration on it from the get go!

 

i replaced the grid heater also back last february and the relay. could it be the fuel rail pressure sensor? thanks for you input I will look into checking the injectors.

 

yes i have oil leaking from the valve cover and i have pressure inward when i set the oil reservoir lid on top with truck running it will eventually tighten the lid on its own.

 

So when you bought the CP3(Injection Pump) did it come with a FCA Valve(Fuel Control Actuator Valve) ? or did you put the old one back on Just wondering?

 

no it is the old FCA

 

I am thinking that is the next thing to tackle. Is there a way i can check this to see if it is bad? I have already spent tons of mula and would hate to keep throwing money at it...feel me?