2007 Expedition - Surging/Bucking while Driving - No Codes - No Misfires

Hey guys, just test drove it again today and took some log data.

Firstly, I tried removing and reconnecting all ECM connectors in the engine bay. No change.
I also tried removing the ground cable, draining the capacitors for a good 10 minutes with a jumper, then reconnecting the ground cable to the battery. No change.
I have NOT cleaned the throttle body. It looks really good and actuates smoothly and without jumping around when the engine is off.

I don't know if this is the cause, but I came across a discovery today after driving it and looking at my log data...
It seems that the VCT Command DC (Duty Cycle) stays high on some runs as my RPM rises above 2000, but the VCTADV (Actual Advance)(and VCTADV2 for that matter...) drops to 0 way before the command DC comes down. I'm now very concerned that I am dealing with an oil pressure problem... (bank 1 falls out before bank 2)

That said, that doesn't jive with the test I did two days ago. I drove it until it started bucking, pulled over, shut it off, pulled the VCT actuator connectors off, started it back up, and started driving again. As soon as I got back on the road, the bucking continued. Drove it a while like that. Pulled over again to reconnect everything. Faults from disconnecting things went away but was still bucking all the way home.

Any ideas? I'm still grasping at straws trying to figure this out. Why would it continue to surge if low oil pressure is the culprit, even when disconnecting the VCT Solenoids?

If the only time it's an issue is with the tire change, would think it is a trans issue. Have an 07 myself and had a misfire, after repairs I disconnected the battery and drained the caps. The trans would not shift smoothly and would buck and act up. From a start I shifted the trans thru the gears manually and did this a couple times, it is not a smooth as it once was but drives good now.

This may be specific to the POS 5.4-3 valve engine.

This was my experience with just what you described. One of the phasers had a broken spring. Replaced phasers, chains, and guides. That solved the biggest surging problem.

But I still have a small amount of surge and since it's ticking loudly, I think one of the rollers came off of an intake valve follower, only partially opening 1 of the 2 intake valves. I'll find out for sure Tuesday or Wednesday.

Neither of these set any codes.

Well, update time, finally.

I drove the truck on and off until about the start of the year. It was nice to have around for the snow... but then I parked the truck for about three months. The battery died in that time. We came back to it and charged it up and drove it around for a bit. Didn't really act up but that has been the normal. If I left it to sit for a week or a month, the first couple drives generally went well, but then the issue would surely return.

That said, a lot of anxiety and stress about potentially spending many hundreds of dollars on this thing led me to just let it sit.

I finally got the nerve (and the time) to get out to my Dad's shop and get the truck in the air. We changed the fuel filter, as it came to me with unknown status and I've had the new filter sitting in the back seat for about a year. So far, no more surging issues. I've been on several drives and even towed a trailer to go get a golf cart for my father. The truck is running and driving great. I'm hopeful that this trend continues. (*frantically knocks on wood*)

I guess this serves as a reminder that when it comes down to it, try to keep calm, change (any and all) easy and cheap to change parts before you let yourself get overwhelmed by thinking you are going to have to tear the engine down and get to replacing internals. Now I have time to schedule the phaser replacement on my watch, not when the truck tells me. I know it will need done sooner than later, so I'm just gonna go ahead and plan for next spring (after the snow season is over again).

Keep it real everyone, and don't freak out. It's probably the easy fix after all. Oh, and sometimes too much information is a bad thing.

Work done:
Drain and flush transmission (with new filter)
New (all 8) one-piece Motorcraft spark plugs
New air filter
New MAF sensor
Disconnect Battery and drain capacitors for ECM re-learn (Second time was accidental)
Fuel Filter Replacement

Update time again. Not a day after my last post, the surge came back. We found an injector (#6) that looked to be leaking out slowly through the electrical connector... so I changed all the COPs and Injectors, but the surge still continues. I'm looking for potential solutions.

My findings: we put a fuel gauge on the truck and drove it down the road until the surging started. When the surging started, the engine surged (without RPM variation) every half second or so. The fuel rail pressure would flick from 70 psi to about 50 psi twice every surge (about every 1/4 second). The pulse in fuel pressure would flash low just long enough to see it on the gauge, but immediately comes back up to about 70 psi... but repeats every 1/4 second.

I'm tempted to replace the fuel pump, but it doesn't feel like that is the whole solution.
I'm also tempted to do a timing job to replace the phasers, chains, guides, rocker arms, vct solenoids, and oil pump (for a high volume oil pump)... simply because the truck is over 190K miles.

I'm wondering if anyone else has experienced this kind of issue. I'm truly at a loss now and am looking for some help.

I don't know if your year has a fuel pump control modual,f150s have them usually cause a no start, or change fuel pump relay. Who knows maybe one of them !!!

This year of expedition (2007) does not have a FPDM (Fuel Pump Driver Module). It's simply driven by a relay controlled by the ECM. And yes, we have swapped all the relays around several times for troubleshooting...
But that was a awesome question.

Also, unfortunately, this year of expedition doesn't have a Fuel Rail Pressure Sensor either.

@OP - Check fuse #74 under the hood. My 2007 had that fuse socket a bit loose. Try wiggling it with the engine running, like you'd wiggle a loose tooth. I had my 07 acting like it was posessed by demons - it was revving for no reason, the tranmission was slipping, it was setting codes that made absolutely no sense (ALL of the sensors failed?) and generally being an all around pain in the rear. Turns out fuse socket #74 had loosened over the years and it feeds all of the sensors like MAF, camshaft position, etc. I wrapped the legs (carefully so as to not bypass the fuse) in aluminum foil and stuck it back in the fuse socket. No more demons.

*EDIT:
It only had codes AS the event happened, once the fuse made a good connection the little bastard would clear its codes since it figure the problem was gone.

@p38fln I will certainly give that a try when I get time to go back out to my parents where the truck is parked currently. It's an hour drive from where I live and I just don't have the space here in the city to park two vehicles currently.

It probably doesn't help that this truck was a fire department's emergency vehicle and the wiring had been hacked up all around.... Mostly for lights. (I already had to re-wire the brights because they were cut into and wired up to flash back and forth)

That said... I'm tempted, with what you've recommended, to change several of the fuses out while inspecting them for loose connections. I also had the idea of scoping the power wires for the fuel pump specifically. Might still do that. I'll be back in a couple weeks with hopefully some results from my testing (once I have a free weekend to get out there).

UPDATE TIME AGAIN!

After testing and checking all of the fuses, I was unable to find any conclusive evidence of an electrical problem at the under-hood fuse panel... but, I do have some updates for everyone!

I had seen that (comparatively to my other vehicles) my upstream O2 sensors were not cycling as fast as I would hope... So, we drove in to changing (all 4 of) the O2 sensors on the truck. They all came out easy, surprisingly, except for the passenger downstream sensor. When we finally got it out, we found that the sensor wires had rubbed against the transmission, causing the copper in the wires to be exposed (hopeful?). I took it for a couple drives and things seemed fine... but, ultimately, the surging returned (and with a vengeance this time).

Armed with a little spare cash and convinced that I was at the point of tearing into the engine to change the oil pump and the phasers, I kept driving it... That was, until last Wednesday. THE TRUCK FINALLY THREW ANOTHER CODE! To be honest, I was so stoked to see the engine light come on, I pulled over, opened the scanner, and pulled the codes. (P0325 - Knock Sensor 1 circuit malfunction). Armed with this new information, I set up a logger and a display on ForScan to watch the knock values on the rest of my drive to work.

The knock values were suddenly very different bank-2-bank, is what I immediately noticed (where they had been very similar before). Needless to say, I got online and found that RockAuto had them in stock, but the ETA was after the holiday weekend here in the US, so I prayed, picked the second cheapest shipping option, and went about my day. (Also ordering an Intake Manifold gasket set) much to my surprise, I got a notification stating that my parts were soon on their way and would be delivered Friday (yes! I could work on the truck over the holiday weekend!).

After some wrenching, we (me and Dad) were able to get the intake manifold out, replace the knock sensors, and we did a quick repair job on some damaged/exposed wiring on the CMCV valve pigtail. After cleaning up, replacing gaskets, and reinstalling everything, the truck has been running great all week! I can't wait to roll this thing past 200k in the coming weeks!

I just thought everyone would appreciate a proper end to this thread and the solution that my particular application came to. So many great suggestions and things to check from you all! Thank you all so much for the help and guidance along the way! I'm so glad the truck is finally doing what it should be doing!