Throttle surge during cruise, accel, decel, idle...

[Blue Oval Guy]

04' Excursion. Bone stock.

The throttle surges at random in any condition. Hot, cold, in gear, in park, cruising, accelerating, etc. Sometimes dies while coasting or stopped in gear. When it acts up, the idle gets choppy or "crispy". Sort of like it has a big cam.
You can be cruising and feel the surge come on and go away while you can hear the tone of the motor change from smooth (no power) to crispy (good power).

No codes right now.

These symptoms have been around awhile, but are progressively getting worse. Acts like bad ICP/IPR. I saw fluctuations between desired ICP and actual ICP on AE. Changed ICP. Old one was dry but symptoms went away for a couple weeks.

Fast forward a couple weeks, symptoms return. Took a look at the EBP for fun. Cleaned tube and sensor. Tube wasn't very dirty at all. Symptoms go away for another week or two.

Symptoms come back. Changed EBP. No change.

On AE, FICM voltage runs a steady 47.5-48.0v through all the surging and "crispiness".

Has black smoke out the tailpipe when its acting up.

ICP (desired and actual) are rock solid through all of this.

TPS is steady. Reads 0% at idle with or without symptoms.

Truck starts right away, hot or cold.

I'm running out of ideas. Any help would be greatly appreciated. This thing is getting dangerous for my wife to drive the kids around in.

 

[Blue Oval Guy]

It's tough to hear but the video in this thread sounds just like my Ex when it acts up. I had found another thread with another video that match my symptoms exactly in my searches on this problem but can't seem to find it now.

http://powerstrokearmy.com/forums/showthread.php?t=39525&highlight=surging

Edit: Here is the other video. At 47 sec. the truck in the vid stalls just like my Ex does.
http://www.youtube.com/watch?v=h5x4UXKK2VQ

 

[Blue Oval Guy]

Little more info.

I've done the jiggle test on the harness running around the back corner of the motor. I've never gotten it to act up this way so I'm really thinking (or hoping) it's not a harness problem.

Back when I changed the ICP there were codes for the EBP, turbo overboost, turbo underboost, and a couple other random codes. I contributed all of them to funky EBP feedback. No codes since the new EBP went in.

 

[suprdzlduty]

Egr valve is hanging open. Take it out and clean it. Better yet look into doing a delete in the near future.

 

[Blue Oval Guy]

Egr valve is hanging open. Take it out and clean it. Better yet look into doing a delete in the near future.

You reminded me that when I did the EBS, I also cleaned the EGR when the problem went away for awhile. I'd forgotten about that.

I'll give it another shot.

I'll delete it here one of these days.

 

[suprdzlduty]

You could leave it unplugged...that way it doesn't open when demanded...not the best policy but will by you time.

 

[Kenbasstx]

I say either your EGR, Or the oil cooler is starting to go south on you. Mine was Idling pretyy nasty like that before I replace my oil cooler and did the EGR delete on it. It would stop idling once I started to accelerate. It never stalled out like that ( thank god ) but I did try to make a trip down to Houston. I only made it an hour outside Dallas and had to stop three times before I stop and turned it around. Did all my deletes, and replacments that weekend right there. After that my truck runs cooler in oil temp, coolant temp, and my oil pressure even dropped a bit which is suppose to be a bad thing but I think it was running too high anyway.

 

[Blue Oval Guy]

I realize this is an old thread but I thought I'd follow up with it.

The EGR cooler ruptured a couple days after starting this thread. I ended up sending this Ex to the dealer due to lack of time to dig into it. Of course they pulled codes and condemmed the turbo, EGR valve, EGR cooler, oil cooler, IPC, and 3 injectors.

I told them to fly a kite on the EGR valve, IPC, and turbo. I knew the turbo over/under boost codes were likely a symptom of whatever was going on and the EGR was fairly new.

They wouldn't install a delete but they would install a Bulletproof cooler. So we did that, a new Ford oil cooler, and all 8 injectors.

It runs good 99% of the time, but every once and awhile it will RPM flare in gear or Park. Nothing bad, but it's there.