I found this under the driver’s side underneath my expedition but don’t know what it is or where it goes

I would have to send a picture its hard to explain

My car has 136000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
Hello. If you have found a loose harness, connector then it may be possible that they go to a component or feature that is not currently installed on the vehicle. You may be able to tell if this is the case by examining the connector or wires. If they appear to be dusty as a result of being unmoved, untouched, then it may be possible that they are simply an extra connector. There are also several relays and modules installed underneath the dash. These look like boxes with harnesses going to them, and can come in different colors and sizes. They will either control the function or power of different features or components of the vehicle. You may be able to identify the specific component by inspecting it for a part number and looking it up.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

The first generation 5.4L, produced from 1997 to 2004, has two valves per cylinder. It is relatively reliable, with only two major faults: excessive timing chain stretch, and spark plugs sometimes blowing out of the cylinder head.
The Ford 5.4 Triton has proven to be an impressive engine that delivers a good balance of performance and reliability. However, there are certain areas in which it can fall short. One of these areas concerns the timing chain, timing chain tensioner, and cam phasing system.
2009-2010 Triton 5.4L

With 300 horsepower and 365 lb-ft of torque, the Triton 5.4L is one of the most reliable F150 engines. Minor problems were still present like crank angle sensor issues and the occasional spark plug broken off in the head, but few repairs were as expensive as the previous years.

Most of the most common problems developed with the 2004-2013 3 valve engine but some problems spanned all engine generations. The most popular issue but easiest to fix, is the ignition system. The 3 valve 5.4L Triton contains a coil-on-plug design.
The Ford 5.4 L Triton engine has been known to have problems with the fuel pump driver module. Due to it`s placement in the vehicle (usually at the rear – on or near the frame), the fuel pump driver module is exposed to the elements. Dirt, water, and salt can all build up over time and cause the module to fail.
TOM: For those who have Ford trucks from this era, the offending engines are the 3-valve 5.4-liter from 2004 to 2007, the 3-valve 4.6-liter from 2005 to 2007, and the 3-valve 6.8-liter from 2005 to 2007.
When Ford introduced the single overhead cam 5.4L 3V Modular V-8 in 2004 in the redesigned F-Series trucks and the 4.6L 3V in the all-new `05 Mustang GT, it was viewed as an upscale compromise between the 2V Modular and the mighty DOHC-4V Cobra and Mach 1 engines.
Ford SVT Lightning 5.4L engine with 380 hp (283 kW) and 310 ft-lb (610 Nm) of torque.
Even taking pre-clean and soak precautions, and working the plugs slowly, we managed to break five of the eight plugs and had to use a Lilse spark plug removal tool to complete the removal of the broken plug tips. The tool worked great, but total time to do the job on our engine was about four hours.
Does Ford still make the 5.4 engine? Yes, and no. The engine, which was first produced in 1997, was used in the F-series through 2010.
In theory, 5 valves per cylinder may offer larger valve area than 4-valver for better breathing. The smaller and lighter intake valves also enable the engine to rev higher without worrying of “valve floating”. The latter reason was especially crucial to high-revving superbike engines and racing motors.
Ford`s 5.4L V8 engine has also had some ongoing issues with its fuel pumps, particularly in the 2006 Ford F-150. One complaint on the NHTSA page was filed in 2017 and reports that the fuel pump control module became corroded, causing the engine on the truck to stall completely.
A well known problem with the Ford 5.4 3V engines is the dreaded `phaser rattle` This happens when the variable cam timing phasers can no longer be controlled by the ECU due to wear in the phaser or lack of oil pressure / volume being delivered to them.
The 5.4-liter V8 engine lasted from 1997 to 2010 in the Ford F-150. And although some versions are better than others, you should avoid the 3-valve V8.
Modular engines used in Ford trucks were marketed under the Triton name from 1997–2010 while the InTech name was used for a time at Lincoln and Mercury for vehicles equipped with DOHC versions of the engines.
Many factors can cause a spark plug to fail; from incorrect heat ranges to improper gapping, to chemical contamination. Yet 90% of spark plug damage claims are due to improper torque. Many factors can cause a spark plug to fail; from incorrect heat ranges to improper gapping, to chemical contamination.
Ford Expedition Powertrain

The early V8 engines feature two valves per cylinder, and the V8 engines in the later generations have three valves per cylinder. The most recent Expedition models are now powered by the 3.5-liter V6 EcoBoost engine, the most powerful and efficient engine to date.

The most reliable year of Ford Expedition in the first generation is the 2002 model year. According to CarComplaints, the 2002 Expedition has received only 400+ complaints and four recalls – a stark improvement over the previous models.
One of them was the GT500`s 5.4-liter supercharged V8. The advanced all-aluminum engine features dual overhead cams, forged pistons, and a roots-style supercharger from Eaton. It produces 550 horsepower and 510 lb-ft of torque.
all blocks them selves and heads are the same… On the heads there are two kinds… ROMEO and WINDSOR… the only difference is the valve covers…
that could mean you have engine damage as the 5.4L is an interference engine. You can have piston and valves that are damaged.
1998 F-Series Engine Specs

The big V8 engine for the F-150 the 5.4L Triton makes 235 hp @ 4,250 rpm and 330 lb-ft of torque @ 3,000 rpm.

One service issue technicians should be on the look out for is late-model Ford trucks (1997 to 2004 Ford F-Series, Expeditions and Excursions) that are reportedly blowing out spark plugs. The problem seems to occur most often on 5.4L Triton engines, but may also occur on other V6, V8 and V10 engines in these vehicles.
Does Ford still make the 5.4 engine? Yes, and no. The engine, which was first produced in 1997, was used in the F-series through 2010. However, it is still used in the E-Series vans the company still produces.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Driver Side Inner & Outer Tie Rods and driver side strut being bent.
ANSWER : From what you’ve described, the damage was most likely caused from hitting a pot hole. If the damage was from a pot hole on the right side, in some cases it’s possible for the force to transfer over and damage the left side as well. If you’d like a second opinion on this, consider YourMechanic, as a certified technician can come to your home to diagnose your car’s suspension system and confirm these suspicions.

Driver side door lock button not working, and passenger side sliding door makes a buzzing noise
ANSWER : Hi there. These door issues are common on this vehicle. Most of the time the main issue is the master door lock switch on the driver door. It sounds like you already replaced that. As for the sliding door problem, most of the time, this is a failure within the door module or it can be a connection issue.

I typically take the door apart and check the connections on the module and inside of the door just to make sure that there is nothing apparent in there. If the connections and the wiring are fine, then I use a scan tool to check the module to see what the inputs and outputs are doing. If you need to have this looked at, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose your door problem and recommend a repair.

I found this under the driver’s side underneath my expedition but don’t know what it is or where it goes
ANSWER : Hello. If you have found a loose harness, connector then it may be possible that they go to a component or feature that is not currently installed on the vehicle. You may be able to tell if this is the case by examining the connector or wires. If they appear to be dusty as a result of being unmoved, untouched, then it may be possible that they are simply an extra connector. There are also several relays and modules installed underneath the dash. These look like boxes with harnesses going to them, and can come in different colors and sizes. They will either control the function or power of different features or components of the vehicle. You may be able to identify the specific component by inspecting it for a part number and looking it up.

Power mirror on passenger side will not retain it’s setting driver side works perfect.
ANSWER : A technician with an advanced scan tool can verify the issue. The mirror system is complex and involves many modules. The Body Control Module is a possible cause, but it’s doubtful; replacement requires reprogramming, which requires special equipment. I would check the driver’s and passenger’s door modules; toggle or move the switch on the driver’s side to see if it causes the problem, and ensure that the mirror glass itself is not loose on the passenger’s side mirror assembly.

Without diagnosing the problem with advanced equipment, the issue is hard to diagnose. A qualified YourMechanic technician can show up to the location of your vehicle with a scan tool to inspect and diagnose your power mirror issue.

Lowbeams on drivers side will not shut off
ANSWER : Hey there. To be completely honest my friend, you might need to go back to the basics and purchase a detailed wiring schematic for this vehicle to determine where the electrical fault exists. Quite often when an electrical fault like this exists, the best solution is to trace every connection to see where the fault is triggered. Most of the time, it’s an exposed wire or ground issue that causes the circuit from the switch to the lights to fail. If you need help here, one of our professional mechanics can come to your location and complete an electrical problems inspection.

Front driver side tire moves side to side when jacked up
ANSWER : If you can move the tire in and out when on a jack then you may have a few different possible problems. The inner or outer tie rod ends may be worn. Your steering gear may also have worn bushings. I would recommend moving tire back and forth while holding onto the tie rod ends to see if looseness is felt and replace any loose components. An alignment will need to be done after repairs.

2012 fusion ddamage front pass side trunk shifted to the drivers side. Is this possible
ANSWER : Request that a professional alignment shop use a tram to carefully and completely measure the unibody and compare all such measurements against the data set out in detail in your vehicle’s Factory Service Manual. Using that strategy it will be easy to conclusively and authoritatively determine if the unibody is damaged. If the unibody was damaged in the collision it will have to be repaired, if cost effective, or obviously the insurance company will have to make you whole on your claim for damage. If you have any further concerns, do not hesitate to contact YourMechanic as we are always here to help you.

On the 4.7 which tensioner plate goes with which tensioner?
ANSWER : The best thing to do is look at the brackets that are to be mounted behind each tensioner and match up the bolt holes that mount the brackets in place. Then install the chains and install the tensioners. Then you can tighten them up. The brackets are different and if they are switched, the chains will not connect with the tensioners hooked up. So if the tensioners are able to hook up to the chains with the brackets on, then they are in the right location. If you need further assistance with your timing chain tensioners and brackets, then seek out a professional, such as one from Your Mechanic, to help you.