Changing Spark Plugs on 91-94 Explorer

[pugsy]

The spark plugs on my Explorer had only been changed twice in the last 15 years. I was the third person to change them, so I know what stuck spark plugs are like. I never broke any off, but I went slow with them, using gradual pressure until the broke loose. When I reinstall spark plugs, I make sure they're nice and snug and not going to back out, but I don't go crazy on the torque.

Does it snow where you live?
My broken ones were rusted to the head and the hex on the plug was so rusted that it wouldn't fit the socket properly anymore...assuming the rest are the same... prolly why no ones ever changed them! lol Don't blame them.

 

[mckrooz]

Thanks for this. Good move on removing the wheel to get to that passenger side plug. It was a cinch after that.

 

[TedJ]

Removing the passenger side tire is much easier than going from the top... You can reach right in there. I thought the explorer was a pain till I did an Aerostar... same engine but its basically inside the dashboard. You would think they would move the coil pack but its still in the same explorer location..

 

[mora20164]

Changing Passenger Firewall Sparkplug

I changed the spark plugs this weekend. I didn't have too much trouble changing this Pain in the ass "SP". What i did was Move the Steering wheel all the way left. This provided enough space underneath the wheel well to reach in pull the wire and change the plug. No jacking up the car and didn't have to take tire off.

 

[Dean403]

Great write up! Very helpful.

A few additional thoughts....

1. Jacking the right side is unnecessary, but helpful I think. Gives you more room to wiggle about.

2. DO NOT under any circumstance forget the anti-seize unless you have no intention of ever removing the plugs. Last owner of my truck changed the plugs (even the rear right) but skipped the anti-seize. Had to use a reefer bar on the socket wrench to get the damn things turning. The one at the rear right was special, and I ended up breaking it in two while removing it.

3. Take a brush or air hose or scraper and remove some of the rust around the plugs before removing them. I had a lot in there - enough that in some cases I couldn't even get the socket in before digging out the rust.

4. Change the wires with the plugs, especially if you haven't done the plugs in a while or you don't know when the wires were last changed. You'll be happy with the results. Trust me - or search the forum for why.

5. While we're on the subject of parts, don't trust the parts counter morons to give you the right plugs and wires. Check then double check before you get messy and start opening things up. The guy I dealt with gave me 4 plugs for the Explorer and 2 plugs for a newer Chrysler 4.7. Funnily enough, I actually own a Jeep with that engine, but having just changed the plugs in there I had no use for the new ones. Cue PITA trip back to Canadian Tire to get the right plugs part way through the job

On a scale of 1-5, plugs is an easy 1. Nothing difficult here, and nothing the novice can't tackle on their own in the garage.

 

[MrQ]

On a scale of 1-5, plugs is an easy 1. Nothing difficult here, and nothing the novice can't tackle on their own in the garage.

Absolutely. This is a very simple task and we now have multiple ways to address changing the rear passenger spark plug.

 

[mora20164]

Question:siezing agent?

I used liquid wrench, but there are tons of anti siezing agents. Does it matter? Is there one preferred more then others?

Great write up! Very helpful.

A few additional thoughts....

1. Jacking the right side is unnecessary, but helpful I think. Gives you more room to wiggle about.

2. DO NOT under any circumstance forget the anti-seize unless you have no intention of ever removing the plugs. Last owner of my truck changed the plugs (even the rear right) but skipped the anti-seize. Had to use a reefer bar on the socket wrench to get the damn things turning. The one at the rear right was special, and I ended up breaking it in two while removing it.

3. Take a brush or air hose or scraper and remove some of the rust around the plugs before removing them. I had a lot in there - enough that in some cases I couldn't even get the socket in before digging out the rust.

4. Change the wires with the plugs, especially if you haven't done the plugs in a while or you don't know when the wires were last changed. You'll be happy with the results. Trust me - or search the forum for why.

5. While we're on the subject of parts, don't trust the parts counter morons to give you the right plugs and wires. Check then double check before you get messy and start opening things up. The guy I dealt with gave me 4 plugs for the Explorer and 2 plugs for a newer Chrysler 4.7. Funnily enough, I actually own a Jeep with that engine, but having just changed the plugs in there I had no use for the new ones. Cue PITA trip back to Canadian Tire to get the right plugs part way through the job

On a scale of 1-5, plugs is an easy 1. Nothing difficult here, and nothing the novice can't tackle on their own in the garage.

 

[MrQ]

I used liquid wrench, but there are tons of anti siezing agents. Does it matter? Is there one preferred more then others?

Each person has their personal favorite, but in the grand scheme of things the real point is making sure that those plugs haven't welded themselves to the head the next time you change them. And for doing that, any anti-sieze compound will work, just make sure none of it gets inside the head.

 

[fordnut71]

you can remove the front tires to get most of them. i do the drivers side 1s from under the hood. then for the passenger side i take the tire off an do cyl 1 an 2. on some explorers iv been able to do 3 also but some iv done it under the truck between the frame rail an tranny.

 

[coolerpooler]

i know i just changed my spark plugs and the best spark plugs to put in is the e3 diamond fire spark plugs they come pre gapped and they cant be bent or anything to ruin the gap. i noticed a great difference in gas milage and acceleration but thats probably also due to the 9mm wires i added and the accel supper coil. the spark plugs i pulled out had been put in in 1999 so they were worn down to a gap of .75 they were so bad they would arc to the heads and you could hear them when accelerating.

 

[FarmTruk]

Hats off you you guys who change these plugs in 15 minutes.

I consider myself fairly competent with a wrench, but danged if it didn't take me a couple of hours to change out the passenger side plugs. They had not been changed in I don't know how long, so they were not eager to give up their grip on the cylinder head.

After jacking up the right side, removing the wheel and fender liner, air box and inlet tube...I still could just barely get to all of them. It's a tight fit, and required a few swivels, extensions, and sacrifice of blood to get them all out.

Thankfully, I'm happy to report that my low rpm misfire under load is now a thing of the past.


BTW...I put the Duralast wireset on to replace my 160k mile OEMs. They didn't seem to fit quite as well as the originals. The clips on the coil pack terminals seemed to require a bit of fiddling to secure them, and even then, I'm not sold on just how "secure" they are. Anyone have same experience, and or better luck with different wireset?

 

[TedJ]

Duralast has proven to be junk in my experience. I had someone buy me a set to install on their Aerostar (same engine) and I wanted to have them return it for the Bosch set (the other option at Autozone), but they did not want to do it. I installed them, and a year later the clip on one of the wires lost its grip on the plug and created a misfire. I ended up re-doing it with the Bosch set which was much better quality and easier to install.

I use the Motorcraft plugs and wires on my truck. I think either the Bosch or Motorcraft wires are fine for a stock replacement. I would not use anything but Motorcraft plugs though (there is a lot of controversy here, some people arguing x brand of of plugs is better, worse, etc; but nobody has ever complained that the Motorcraft plugs did not work right)

 

[cyrix9445]

nice writeup! I will definitely be change my plugs next weekend

 

[jordan1948]

How much torque specifically should be used on the spark plugs?

 

[MrQ]

Basically I did one and a half turns after finger tight. You don't want to strip the heads. As for the actual torque, I'll have to get back to you.

 

[cyrix9445]

I changed my plugs and wires the other night, i didnt use any wobble sockets, just the sparkplug socket and a small extension, but back passenger side plug i had to get from the underneath the truck, VERY easy job

 

[Exploderman09]

Thanks

I was having trouble with those passenger side ones too, wheel well works well though.
Nice shiny manifold too, I just powerwashed mine!!

 

[jordan1948]

Basically I did one and a half turns after finger tight. You don't want to strip the heads. As for the actual torque, I'll have to get back to you.

Found it. It's 15#

 

[MrQ]

Found it. It's 15#

Added. Thanks!!

 

[jchamzc]

Thanks for the write up.

I had never changed spark plugs before today and your right up gave me the confidence to tackle it.

One note: on my 93 sport, the socket needed was a 5/8 and not a 5/16.

Everthing went well. Thanks again.