Introduction: Making an Inexpensive Broken Spark Plug Boot Removal Tool

Picture of Making an Inexpensive Broken Spark Plug Boot Removal Tool

This instructable is to show you how to make your own inexpensive tool to extract that broken boot off of the spark plug so you can continue with your tuneup.

For you DIYers that work on your own vehicle, there's nothing like replacing your spark plugs only to find out that the boot on the end of the wire has stuck to the spark plug and has detached itself from the wire/coil pack way down inside the spark plug tube.  There is a commercial tool that costs around $30 but who carries that tool locally? 

Step 1:

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Using a 6' garden stake with a steel inner core purchased for about $3 at your local hardware store (Ace Hardware, Lowes, Home Depot), cut off about 12" from the blunt end with a hacksaw.  The one I purchased was GardenPlus 6' garden stake, item# 0093249, model# 831138 from Lowes.  You can make about 6 tools for the $3 investment.

Remove the inner core end plug from the blunt end of the cut stake and discard the plug.

Step 2:

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Using a box knife, score the plastic to the steel inner core about 1½" from the blunt end. 
Using a lighter, heat up the plastic until it starts to soften and peel back.
Careful...the steel core will be hot!
Use the box knife to remove it from the steel core.
Split the end of the tool just a little to allow the tool to expand over the spark plug.  I used needle nosed pliers inserted and rotated it to widen the end a little.  The weld cracked on the end and a quick test fit over a used spark plug confirmed it was a good tight fit.

*Update* Using a grinder, I was able to gently roll the tip against the grinder wheel to put a sharp edge on the tip so the tool will cut through any fused rubber easily!

Step 3:

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To use the tool, spray the end with some spray lubricant (WD40 works).

Place the end of the tool over the spark plug and push down over the spark plug.  It may take a little effort but it should easily cut through the fused bond.

Remove the tool and the broken boot.


Remember to use a little dielectric grease on the inside of the spark plug boot to keep this from happening in the future. You don't need a lot...just a light coat. You can find the little packets of dielectric grease in your auto parts store near the front counter...or you could always ask. ;)


alphaa10 (author)2017-10-22

Nice solution-- I found the presentation logical and detailed, but a little vague at the beginning in depicting the problem. A photograph of the (removed) plug and its stuck boot might be helpful in understanding what must be cut through.

Your photography is outstanding-- what kind of lighting and camera / lens did you use?

BamZipPow (author)alphaa102017-10-22

Thanks for the reply! How did you happen across my instructable? Did you make the tool?

In my first and third pictures, I posted the simulated boot fused to the spark plug along with a comment box for each plug. You would have to click in each box to read the comment.

As far as photography goes, it was just a simple point and shoot Canon or my Samsung cell camera. Lighting was with a simple Dazor desk lamp or existing ambient light with flash.

zultron made it! (author)2016-12-26

THANK YOU for this magic tool! Depicted in the photo below, removing the stuck boot took mere seconds: push tool onto plug with stuck boot; rock tool around in circles; remove; the boot comes out with the tool!

Subaru Foresters have boxer engines where the engine's valve covers and the body's frame are just two inches apart, barely leaving room to get a wrench onto the plug, which is deeply nested between two overhead cams. The second photo shows how the socket, extension and wrench must be disconnected in order to be put in place. Not just any plug boot tool could also fit into this awkward space. This tool did the job instantly, with cheap and available materials. Thank you, thank you, thank you!


BamZipPow (author)zultron2017-03-07

I'm glad my tool was able to help you out. How did you find out about my Instructable? Google search? A mention in a forum?

zultron (author)BamZipPow2017-03-22

Found it through Google. It's the first hit on a search for "spark plug stuck boot tool", which must mean a lot of other folks have also had success with this Instructable and linked to it. Thanks again!

BamZipPow (author)zultron2017-03-22

If you visit a Subaru forum, don't forget to point them this way so they won't be at odds trying to get that broken boot off.

bmaverick (author)2016-07-26

Nice. After reading about this problem on different vehicles and makes, making one of these tools is a must. So I did.

NOTE: When placing a new C.O.P. boot onto the plug, use dielectric grease to prevent this from happening on the next plug change go around.

zultron (author)bmaverick2017-03-22

+1, pointer to dielectric grease in the instructable would help others avoid this problem next time.

BamZipPow (author)zultron2017-03-22

Noted and updated!

davidj31 (author)2015-07-18

there have been times in the past I could have used this. I drive a diesel now but will keep it filed away.

sgthirkell (author)2015-07-17

This was an instructable that really helped as I was totally lost as to how to get the car back on the road. Thank you so much.

I am so glad there are people willing to share knowledge like this.

BamZipPow (author)sgthirkell2015-07-17

I'm glad my Instructable was beneficial to you. Just out of curiousity, how did you find out about this?
I made this tool after fighting with my neighbor's broken spark plug boot in his truck and didn't find any easily accessible tool to the common person. I keep this exact tool in my truck at all times just in case I'm trying to help someone else change out their plugs and find another broken spark plug boot.

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