I posted before on this issue but it seems to have gotten lost in the mix.

01 X with 7.3
from a cold start the X runs perfect. After running for about 10-15 mins the issue can show. It will buck, surge, but is so very instantaneous. It only happens between 1400-1700 rpms. If I push the pedal it goes away. If I let off a little it goes away. I have tried a potentiometer (fuel pedal) in this vehicle...no difference.

Someone suggested I try a cps ....the one i removed was black and the new one is gray....I installed the other night and last night while road testing it seemed to have done something ...because it did act like it had a tad more zip...but was still acting up on occasion...just a little different. I am posting a video here to show what is going on. Something to note, after the cps change I did not do a battery cable off for 30 min procedure...and in this case it may not matter...no?

I will be trying the unplug the icp sensor once and see what happens when i do that. There is no oil to speak of on that sensor or there of.

My ipr has the thin nut attached. I don't understand the nut on that sensor but it is there. It does appear to be a bit corroded ..again I don't know if that means anything.
Thx for look at this and any contributions.

 

It may be good to stay close to the original thread to see what has been brought up and what has been done. Many will know what you are talking about in the post above, some may not. You seem to have ran this a month with the same problem. How long has this been going on?


https://www.ford-trucks.com/forums/1...ecialists.html

 

I can't tell what's going on in your video, but I've never had much luck with videos. Was there an audio cue we were supposed to hear, or just notice something with the tach?

Does it do this every time you drive at those rpm's? What about different speeds (gears) at the same rpm? What speed is this happening at, and does it have to do with your torque converter locking/unlocking? What happens if you set the cruise control to those rpm's and don't even touch the pedal at all?

 

The key here is that it appears after the truck warms up.

Oil gets to temp and thins. Injectors, IPR, ICP
Transmission fluid: TC slipping?

No codes are present?

Can you duplicate the symptoms in park and just revving the engine to 1700 RPM?

 

I had a problem that was similar to this with loose injectors, but knocking was part of the symptoms. It sounds like a tune with twitchy resolution at that throttle position. Stock tuning?

 

^^^^^^^ This is important.

A vast majority of the time the IPR is to blame. Problem is it happens so fast that you won't see it on a scan tool. It's happening too quick to even throw a code. Usually I don't like to recommend throwing parts under the hood without a proper diagnosis, but in this case you won't be able to pick it up on a scanner anyway.

Replace the IPR and see if the problem goes away.

 

I have no oil showing on the icp plug or there of....although i have not tried unplugging that sensor yet.
no codes present
if i do a rev of the engine while sitting still at times I can get a hiccup...or a lightning fast blip if you will. if i rev it...and rev it again..and again...on the second and third rev it will not hiccup or blip. I have to wonder if once the oil is moving well after that first rev then it stops if something is related to the engine oil and such on this.

It will also at times act like half the cyclinders are not firing...for about 3-4 seconds. if i let off all 8 cylinders will fire. instantly. That half cuclinder not firing thing does not happen often but it happens.

I am thinking all the symptoms are tied together on something.

 

Is the under valvecover harness coming loose?

 

That last description made me immediately think of this as well.

 

I too would agree that the UVCG's sound suspicious.

 

If it was the harness under the valve covers, the OP would most likely have a code by now.

Electrical issues such as that tend to pop a code very quickly. On the other hand, a sticking or mis-behaving IPR that doesn't maintain a proper oil pressure for a quick second or two won't trip a code, because the PCM is programmed to monitor that oil pressure for a specific amount of time before throwing a code.

Just some food for thought.