For those with a 4.0 SOHC engine in a later generation Ranger you know what a hassle it is to change the spark plugs on the passenger side of the engine. The following worked well and cut time and hassle out of doing this plug change. Step One - remove the air filter box: Now this is a big pain because the floor of the box is secured to a metal mounting plate bolted to the engine bay. This is done by plastic extrusions at the front of the floor of the box slipping into rubber grommets in the metal plate. The traditional removal technique is to spray WD40 on the grommets and wait 10 minutes for the grommets to soften. Then, pull and twist and grunt and strain, to have the thing suddenly let go and smash your hands against something sharp in the engine bay. To avoid this, take a 3 foot long traditionally shaped wrecking bar and go under the truck. From about a foot back from the radiator, snake the curved, wedge shaped end of the bar into the joint between the metal plate and floor of the air box. Pry and push a bit until you can get the end firmly wedged in place. Then, twist the bar 90 degrees. This will separate the plastic extrusions from the grommets in about a minute or so of work. Go back up top and pull firmly and the separation of the floor will be complete. From there, the backside of the box eases out of the grommets in the side of the engine bay. Took about 7 -10 minutes to remove the air box. Step 2: Unplug the electrical lead to the windshield washer pump. Remove the 2 bolts (10 mm) and two nuts (7/16ths) holding the coolant tank and windshield washer fluid reservoir to the engine bay. Remove these as a single unit from their position and set on top of the intake. This opens up room to get to the numbers 4 and 5 spark plugs. Step 3: remove and replace plugs 4 and 5. Step 4: the dreaded sparkplug number 6. There is no easy way, but there is a less difficult way, to remove and replace this sparkplug. There is a flap attached to the inner fender shield on the passenger side. This flap can be moved a bit, plus there is a square opening where the flap and inner shield meet. This is the most direct access to the plug. If the sparkplug boot was greased with dialectic grease, here is where that pays off, as it is a hassle to get the right angle to pull off the boot. If there is no grease, the boot wants to stay on the plug. The plug angle is such that a ratchet and extension will not have a straight line to the spark plug. If you put a universal joint type piece between the plug socket and the extension, the angle of the bend in the universal will not allow for a 180 degree or more rotation of the extension. Hence, bypass all of that and get a 3-4 inch stubby ratchet. Put a one inch extension on it and attach the spark plug socket. Put the plug in the socket and then come down from the side of the engine and snake the ratchet/socket plug combination down to the spark plug hole. The stubby will be short enough to operate the handle and also fit within the space allowed when being in line with the angle of the spark plug. I recommend anti-seize compound on the plug threads and dialectic grease on the porcelain of the plug so that the next time you change the plug you will not have problems removing the plug. With so little room to work, you don't want anything to seize up. The stubby ratchet is what makes this job easier. Remember to thread the plugs in by hand until they are started, so you don't cross thread them. Step 5 is to re-assemble all that was removed. It took me about 4 hours to change the plugs, and learning by trial and error (and internet research) to come up with this methodology. My garage floor is re-done with two-stage epoxy garage floor paint, with an epoxy clear coat, then wax. I can slide around under the truck without a dolly just cause the floor is slippery. makes it easy to move around under the truck. I hope this helps someone. Learning about the pry bar and the stubby ratchet should take a lot of frustration out of this job.

 

I wish I would have seen this before attempting to replace my plugs without advice. I got the front and middle plug replaced with great effort without removing anything. That back plug - no way! I removed the passenger side fender shield and honestly I think all three plugs would be accessible without removing anything else.

 

I have cut access holes in wheel wells on several vehicles to gain access to spark plugs and even exhaust bolts.

No reason not to, IMO it actually increases the value of the vehicle, lol.

If just cutting a round hole use a rubber expansion plug to seal the hole.

If cutting a square or rectangle hole you can seal it with a plate or hit a wrecking yard and cut out as much of a wheel well as you need to make a plate, with the same curve.
You can use same push and pop fasteners to hold them in place or whatever you like.
But go BIG, never read a post complaining about have too much room to work.
"jeese can you believe how easy it is to change #4 spark plug, they should make the Power Steering pump way bigger to block that off", lol, nope, never read that before

Vehicle designers don't care about access so you have to rethink their designs and make it better.
They would have added the holes if it was free, but it isn't, you need to spend the time and labor doing it.

 

I use plug socket ans and swivel and go though fender well ,can do all six in about 45 minutes