My 1997 expedition 5.4 4x4 after hooking my ground wire-to the hot lead on my battery it sparked and I removed it then I did it again realized I hooked it up wrong. Then connected everything up the right way, so after that my transmission has no power to it, the car won’t crank unless jumped and runs strong it will drive but stuck in 4th gear unless Manuel to 2nd when driving in 2nd and 4th gear it rides very smooth my speedometer stays on zero and odometer is not working either it’s giving me these codes P0755 P0750 P0743 P0708 P0141 P0161 I checked the live data on the last 2 codes(O2 sensors) they did not have a reading
As far as the car not starting. I’ve changed the starter solenoid still just a clicking noise from the fuse box
im thinking maybe it’s PCM not letting the car start because it sees another problem?
I’ve been testing/researching for almost 2 weeks and I am out of ideas and can’t seem to find a problem like mine?
any ideas or suggestions?

 

Ouch, This not going to be very fun and likely your back account won't like you after.
I would start by checking each fuse with a meter. The PCM does not like to be hooked up backwards.
It has a lot of solidstate devices in it that can be badly damaged by reverse current.

What part of the state are you in?

I can see if I have the correct Ford workshop manual for it but it's going to be a slim chance.

 

I have a New PCM on its way bought it in Vancouver Wa. at all American Parts
for $70(includes shipping) I checked every fuse with the volt meter and they are all good. I also checked the ground on the engine and around the engine bay and it has a good ground connection
BTW I’m in Sequim Wa, Port Angeles Wa, area

 

I had hope you might of been a little closer. I am over here in Tacoma.

There are also some diodes in the system that should also be checked.
I have not found the disk I need yet
Found it. Now to get my laptop setup so I can upload files for you
Unless you want to come over this way for a copy.

 

How exactly do I test those diode‘s? Would I drive my Expedition over there and have you test them or is it something I can do here at home?
(I was just in Tacoma earlier today:/ )

 

Well crap.
Do you have a meter? Even one of the cheep ones at the home stores will work.

I am going to give you a Youtube video to watch.

Big Clive is good to watch for things like this.

This is what the diode symbol looks like and that is how it would look on a meter.

 

So I bought used PCM from a Wrecking yard
I installed it and the car has the same problem so basically nothing improved
im thinking it’s maybe the wire harness?
and is there a TCM for Expeditions?

im leaving for a week. when I get back I’ll do more testing and I’ll let you know what else I find!

I didn’t test the computer because I had the newish PCM coming
I watched the video. good info in it

 

Do you have the OBD2 port in this?

 

I do
I also just bought a Haynes repair manual for my rig and it has some other test I can run here at home

Having this Manuel will help me find the problem!

 

I have found over the years that Haynes is lacking. Even worse is Chiltons.
Oh and BTW Haynes now owns Chilton.

The best manual to get is one of the retired Ford Workshop manuals.
You can find that on Ebay.
This is the one you want. >>> https://www.ebay.com/itm/25399151487...wAAOSw0vJb9Ave

You want to make sure that it a genuine Ford Workshop. They will be on a red and black DVD and not be a single PDF file.

The Ebay search terms I used were >>> "1997 Expedition Workshop Manual DVD"

 

I finally figured it out!!!!
I was looking at my code and it basically gave me Transmission failure then I look at the transmission wire harness then I back tracked to the harness plug and I found out I didn’t plug the harness back in all the way the last time I worked on the car!! I thank God it was nothing more then that!!

 

Good that you found it. You still might want to pick up that DVD I linked to on eBay.