6.0 surging while stoped at red lights

[mx730md]

my 04 has started to surge a little bit when i stop at red light while in gear isnt as bad if i put it nuetrual but it still there on the rpm gauge you dont see it but i can feel the miss and hear it once moving there is no miss aslong as the truck moving no miss from idle to wot ? whats the deal what should i monitor have edge insight cs fcim dips down to 47 but 99% of time it 47.5-48 temp wise everything good voltage good? what could it be i hope nothing expensive

[HAM_RADIO_MAN]

Look at ICP pressure and IPR demand percentage. Some times if the ICP sensor is going out or you have a high pressure oil problems the IPR demand percentage will be all over the place. This will cause some differences in injector operation and timing and those show up as surging. Excess ICP pressure at idle will cause the injector timing to very slightily advance. Here are normal values for your reference. See the t-shoting guide in my sig for more info.

Q: What are normal ICP and IPR values ?

A: Cold engine low idle ICP = 806psi IPR 29%
A: Cold engine high idle ICP= 960psi IPR 33%
A: Warm engine low idle ICP= 585psi IPR 24%
A: Warm engine high idle ICP= 735psi IPR 28%
A: If your engine requires a high IRP percentage to get the same or lower ICP you might have an internal high pressure oil leak

[mx730md]

thanks i might have to update the cs i dont have icp or ipr values. i think i have icp voltage i checked and it when back and forth 1.0 -1.1 does that help at all?

[HAM_RADIO_MAN]

I am guessing you have about 750PSI icp. Here is a chart that refrences ICP voltage vs Pressure.

PSI Volts

200 0.4v
400 0.73v
600 .96v
800 1.2v
1000 1.4v
1200 1.6v
1400 1.9v
1600 2.1v
1800 2.3v
2000 2.6v
2200 2.8v
2400 3v
2600 3.3v
2800 3.5v
3000 3.8v

[mx730md]

is that good or bad? that also proable about 100-150 oil temp i check it tomarrow at operating temp

would it be ok to drive ? i only does it stoped once moving it runs and sounds great no power lose

[HAM_RADIO_MAN]

I am sure it’s OK to drive although it seams kind of high. You really need to get some data on the IPR. With a warm engine at idle is it steady or does it jump around a lot? Does the value change with engine speed as you drive. I am thinking your IPR might be stuck 1/2 open.

[f250ghost]

Hmmm mines been doing this lately at first start up...only for about 30-45 seconds. I'm thinkin ICP (for mine at least) but this will be the 3rd one I've replaced!

[HAM_RADIO_MAN]

Originally Posted by f250ghost

Hmmm mines been doing this lately at first start up...only for about 30-45 seconds. I'm thinkin ICP (for mine at least) but this will be the 3rd one I've replaced!

You have other problems, a truck should not eat ICP sensors. Have you ever replace the pigtail for the ICP sensor? Do you have any data?

[f250ghost]

Originally Posted by HAM_RADIO_MAN

You have other problems, a truck should not eat ICP sensors. Have you ever replace the pigtail for the ICP sensor? Do you have any data?

I think we've only replaced 2 sensors...this will be the third one put in. I haven't hooked it up to a scanner yet...but I have a small oil leak also...i think the sensor is leaking.

[mx730md]

well today when warm at lights it about 0.8 runing at 60mph at around 1800-2000 it about 1.8-2.0 wide open it goes about to about 3.8-4.2

my cs wont read the ipr or icp values