Four weeks ago i bought my first Excursion, a 2002 with the powerstroke and really do like it. We had an Expedition with the 5.4 and tow package but it couldn't handle pulling the camper in the mountains during the hot summer. I have a couple questions that I'd like to see if someone can answer, in no particular order. I have searched on this site for a few weeks, but coming up a little short.

On the drivers side of the engine bay, where the harness exits the firewall, there are four wires protruding from the harness. One red, white, blue and black that are cut and floating there doing nothing. No idea what was there or removed and the PO isn't any help.

When the truck is cold, it is slow to get up to speed. Does the pcm limit fuel while the coolant and/or the trans temp is low?

The torque converter does not lock. Should i use another trans harness end and test the resistance in the solenoid pack that way, or can i check it back at the computer? The fluid is good, and there are no codes at all. The temp never goes past the middle of the gauge. If its not the solenoid pack, what is the next thing to check? How do i check the valve for that? The trans doesn't appear to be leaking. It shifts normally and otherwise works fine. I'm trying to test and rule out the simple things in a logical way.
Which sensors can prevent the lockup?
I do have an ohm meter and a background in electronics, i know how to check wires for continuity but don't know which ones to start with. I do have the pin out for the trans harness end.

The third brake light is working as it should.
Will a clogged or old filter cause this issue with no other issues present?
Is there a warming system for the fuel?
Thank you.

 

“On the drivers side of the engine bay, where the harness exits the firewall, there are four wires protruding from the harness. One red, white, blue and black that are cut and floating they’re doing nothing. No idea what was there or removed and the PO isn't any help”.


Those wires were put there by Ford to add accessories and you don’t not have to make a hole thru the fire wall, they are thru it all ready and you can find them under the dash in the steering wheel area Great for adding additional lights Hope this helped. Good luck with your Ex and welcome to the club.

 

Welcome to FTE and The Excursion Owners Club!

The wires are what's called "customer pass through" wires. They put those there so you wouldn't have to run wires yourself through the dash and damage something.

If the torque converter isn't locking up, it may be related to a chip on the PCM, the shift solenoid pack, wiring harness, balance body, or seal on the input shaft. It's best to have a reputable transmission builder sort out that issue as it's most likely something within the trans itself.

You should consider a BTS balance body snd 6.0 trans cooler. Both mods are drop in and are upgrades that greatly prolong the life of the transmission.

 

just curious? what do you mean 'couldnt handle'? A coworker had a early F150..towed his trailer and was sad because the diesels left him in the dust..machismo thing..i told him keep the f150 but he bought a 6.0...after 3x being towed back because of breakdowns..he sold it...was the 5.4 just slow? or overheated?..or?

 

My 5.4 just didnt have the power to pull it up the long grades of Wyoming into a headwind at 95f. It would constantly want to downshift and rev to 4k or more. Once it popped the top hose off. Changing the fan clutch fixed the cooling issue but it never overheated before that or after that while still being under powered. I used high octane gas, new air filter, new plugs and coils. My cummins has 587k and never gave me trouble with hills or mountains. But i needed the space inside and more seating than the '95 club cab has. I like the 7.3 far more than the 6.0. The cost of bulletproofing the 6.0 plus the labor is prohibitive for me. The mileage of the 5.4? 7.5-9.0 mpg with a trailer weight or 2500lb. It is fairly tall and flat fronted though.

 

I believe it.. plus that altitude.. Tritons are spinners, and if you tow often it can get annoying i bet. I see some v10’s in mobile homes die early.. have a great week
The fuel mileage isn’t bad though.. for the work it’s doing

 

The wires are great for small stuff, but not thick enough for many accessories. If you do wire up accessories, I’d go with an auxiliary fuse block under the steering column.
Have fun with your new toy.

 

@c600wrecker Your 5.4 must have been one of the older ones, 2V engine, the 2V 5.4 is a dog for towing, but the 3V is a champion, actually makes the 2V 5.4 seem like a v6 by comparison...

I have 2 of the 3V 5.4s in Expeditions, a 2005, and a 2009 and they have tons of power in the hills or offroad, but i drove several 2V models and they feel like they are made of lead or something by comparison, the 3V heads just have so much extra flow and efficiency that its like a whole new motor.

Excursions never got the 3V motors so obviously that is irrelevant to this discussion however.

Im actually quite surprised nobody has done a 3V V10 or V8 swap on an excursion, especially since pretty much everything needed is available, the parts, and the knowledge are all there, 2V to 3V swaps are crazy popular in the mustang world, several write ups, its actually not that hard, everyone just gets afraid of doing it due to the electronics, which is also, pretty stupid easy, once you figure it out, you could do it all over a couple of weekends.

 

Hate to break it to ya, but the 7.3 won't be a speed demon towing up a mountain. It'll tow it better than your 5.4 Expedition, but it's not gonna win any races. Definitely shouldn't have to worry about overheating with the 7.3, unless your camper is huge. I've driven a 2v 5.4 and a 3v 5.4, both were in super duties, both were turds.

On my 7.3, especially in the winter, I like to let the truck warm up enough to where the temp gauge just starts to creep up before I take off. They're gonna be slow when it's cold. Old diesels don't like cold weather. If your excursion is totally stock, it could be the EBPV (Exhaust Back Pressure Valve) is closing. This is programmed in the pcm and totally normal. It's basically a valve on the exhaust side of the turbo that will close to help the engine warm up faster when it's cold outside. When it closes, the truck will feel slower. Also should hear an audible hissing noise when it closes, it will be especially noticeable if you've got an aftermarket exhaust.

If the converter is not locking, you could have a chip or just a single tune on the pcm that makes it not lock. If it's totally stock, I'd get a trans shop to look at it. The converter not locking could also be contributing to the truck feeling slow when it's cold. I know when I had tunes on mine that didn't lock the converter in 3rd gear, the truck was a dog.

 

BTW, there is a trick to turning the 3V 5.4 into a little monster, canned tunes help a little, but you actually need to talk to a reputable custom tuner and do the following:
Force Traction Control Off
Force Torque Management Off
Disable Throttle smoothing

Once that is done, the engine is essentially un-chained, and actually drives like it has a cable driven throttle, and not like a throttle by wire as much, lots more torque, lots more pull when you stab the gas.

Ford really REALLY hobbled them in the factory tunes so people would not go wrapping them around trees, or spinning out of control, a fair amount of low RPM torque is left on the table due to those 3 settings being enabled, ive done this tuning on both of my Expeditions, and man what a difference with just a tune, engine wise they are both bone stock other than K&N drop in filters.

It also works on vehicles with manual trans, my 07 GT had the same 3 settings turned on, just to less restrictive values, disabling them on the GT netted similar results. The throttle by wire is actually capable of driving well, if you take the hobbles, and handcuffs off of it...

 

I mean I guess they can make decent power, but then you have the reliability issues. I’d much rather have a 5.0 than a 5.4. 5.0s seem to have less issues and waayyy more aftermarket support. Cleetus McFarland on YouTube has/had a 5.0 F150 that with just a supercharger, e85, and tuning made almost 900hp to the wheels. I don’t believe a stock 5.4 would handle that.

 

Reliability issues? the 5.4 is one of the most reliable engines there is as long as its taken care of, they routinely hit 300K miles, my 05 Expedition has 220K on it now, and other than tune ups, and maintenance the engine is original, and doesn't even use a measurable amount of oil on the dip stick between oil changes. Previous owner didn't even take care of it that well, blew 4th gear out of it trying to pull a big travel trailer up a hill in overdrive, hence i bought it cheap and fixed the trans. My 09 Expedition has 180K on it, and other than the alternator, its original.

The V10 is a 5.4 with 2 extra cylinders, also bulletproof reliable if properly cared for, V10s can crank high rpm all day long and also routinely pass 300K and onwards.

As for the 5.0s they are designed to a different spec, most are built for 11:1 or higher compression which forces you to use upgraded internals, usually forged, hence they can be beaten on even harder.

My Excursion's original motor had 200K on it, and ran perfect, no oil loss, but a shop doing the plugs stripped 2 of them when they put them back in and they blew out only a few miles away from the shop on the way home, I decided to just do my motor build then, since it was down anyway, no point in repairing a 200K+ motor when i was already planning to build a monster for it.

 

Can we get back on topic and take 5.4L thread elsewhere? It's interesting but not needed here. Thank you.
jo7.3, thanks for the exhaust valve answer, i didnt know they had one.
also, thanks to the folks who told me about the passthrough wires. I was worried the PO had hacked stuff up.

As far as the trans goes, I live 45min from the nearest city, so I'm trying to rule out the easier things and go from there. The nearest REPUTABLE trans shop is nearly 2hrs away but i wouldn't trust anyone else to rebuild it. I would be installing myself anyway. I'm going to try a local garage thats an ASA certified MM and see if he has the capability to check line pressures during operation. He's a relative somewhere in the family tree and does the work i don't like to do when i get swamped with my own work.

 

Do you have a tuner or is the excursion all stock? I’m pretty sure all 7.3-4r100 combos had the converter lock-up in 3rd and overdrive. Especially with yours being an 02, that should have one of the better factory shifting strategies.

Normal shifting should go 1-2-3-converter locks in 3rd-then 4th. When it catches overdrive(4th gear) the converter should lock up almost as soon as it catches. On the other hand, when the converter locks in 3rd, it’s almost going to feel like another gear-it’s not gonna lock up as soon as you hit 3rd.

A lot of people will delete that exhaust back pressure valve as it gets rid of a potential oil leak. But if it’s still working fine and it doesn’t bother you, I wouldn’t worry about it.

 

I do not have a tuner on it. The trans sounds like it operates very close to how the one in my dodge does.

would a tuner allow me to monitor the lockup, or is that beyond the scope of what they can do?