6.0 surging idle

[capcalvin]

As the title says, my truck has a intermittent surge in the idle. Idle jumps up 50-100 rpm. Sometimes at a stoplight in gear and truck wants to lunge forward. All systems check out except the FICM. (44-46v) on cold start up. Goes up to 48v occasionally. Brand new (reman) injectors. Brand new icp sensor and pigtail. Truck is running 100% better than a week ago prior to injectors. Idle is extremely smooth and plenty of low end and high end power. Engine is running amazing! Just this stupid idle surge. I have the 58v FICM coming from swamps. Should be here monday. Do yall think the FICM might help with this surge? My only other thought at this point is IPR. ICP and IPR duty cycle both check out. I'm hopeing the FICM will solve this and I'll be done spending money for a while. Any thoughts or suggestions? Thanks!

[capcalvin]

Ok, engine is still surging intermittently. This morning it did it for the first time in a week. Seems to be getting more frequent. I know everyone says if your HPOP goes, it just goes with no sign. I am stumped. HPOP is my only other thought. I watch the ICP and it flucuates as the idle surges. The other issue that I've had since I've owned this truck, is it starts differently ever time I start it. Sometimes it fires up quick, sometimes it rolls into a run. Hard to explain. Not a long crank but it starts and kind of stumbles up to idle. Now when I load my xtreme race tune it does not do this. It fires up very quickly in a snap. I do notice that the ICP is quite different when I run this tune. Recently I have installed 8 injectors, new harness, FICM, ICP sensor and pigtail and IPR valve. I know the 03 HPOP is known for failure more than others. Does it act differently when its about to fail? I would like to order the billet adrenaline stock output HPOP from dieselsite if this is the issue. Any input is appreciated. Thank you!

[cwa502]

my 04 does the same thing and now has intermittent idle drop when clutch engaged and has died a couple of times.... any help out there?

[QMartinez]

My 03 has the same idle symptoms when warm.

[capcalvin]

Mine hasnt done it in over a week. I'm just not going to give it anymore thought until it causes real issues. Other than this, mine is running perfect. I'm certain that its high pressure oil related. My next reliability upgrade will be the adrenaline stock output HPOP. Just don't have $1,000 to spend right now. Maybe this winter sometime.

[bigbadry]

I have an 03 and it does the exact same thing. I was thinking it might be the fuel pump spring but I'm not sure. I am going to throw one at it and see if it helps

[flipp29]

my vote is for the ICP! my truck did the same thing. big pain the change. went at it from the bottom and had to remove the heat sheild on the back of the engine. Oil from the turbo drain tube soaked it!

[capcalvin]

I doubt thats the cause. Though its a good Idea to do anyway. You should check your fuel pressure before and after and see what the difference is. I have the updated (blue) spring installed and my fuel pressure reads 64psi at idle. Never drops below 60psi even at WOT.

[capcalvin]

Sorry, should have quoted bigbadry on that reply. Flipp29, I think you are right in thinking its high pressure oil related. ICP often is the culprit on this one.

[capcalvin]

But our 03's have the early HPOP design. So thats always a possibility also. Especially after you've replaced everything and it still does it. Knock on wood, going on two weeks here since its last done it and running perfect.