Spark plug broke in hole

Asked by Trb129 Dec 20, 2017 at 06:32 AM about the 2002 Chevrolet Trailblazer LT RWD

Question type: Maintenance & Repair

Changing my spark plugs and it broke and
dropped debris in the spark plug hole I've
been driving it for about a week now and all
is well except for I'm throwing a misfire in
cylinder 3

12 Answers


Compressed air or a shop vac may help get the broken parts out of the hole. Were you using a spark plug socket that was missing the rubber porcelain protector?


Also, was there any noticeable noise coming from that cylinder as a tick, or knock? May have to check the compression in that cylinder. A new spark plug was installed I assume...check to see if it is firing.

It broke in Cylinder 6 but the misfires in cylinder 3 yes new spark plugs were put in


Then there is sill a problem with cylinder #3. Check the plug to see if it is firing, it may have a bad coil on it since it is coil on plug set-up. If you had a miss-fire before changing the plugs, you may have to check the compression.

1 people found this helpful.

The boot is f***ed up for sure...what would cause it to do this?


Looks like that could be the problem. You can just get another boot from the parts store to try. Usually what that is from is the coil/boot not installed properly, just jammed on down onto the spark plug without any care.


What helps is using some dielectric grease or some sill glide on the inside of the boot so you can slide it onto the spark plug easier, and feel for the connector snapping onto the spark plug.

1 people found this helpful.

You should use anti-seize on just the threads of the spark plugs especially if the heads are aluminium


Agree with olds403, anti-seize needs to be applied to the threads of the spark plug before instillation on aluminum heads, which your engine has.


Anti-seize should NOT be used on most brand name spark plugs as there is a factory coating that does the same thing. Anti-seize messes up the torque readings and if a spark plug is torqued to spec with anti-seize it will be over-torqued. This goes against the normal thought process regarding spark plugs in aluminum heads, but that is the way it is now days.


Thats why an experience mechanic should be changing the spark plugs. This neck of the woods we use anti-seize on the plugs. The aftermarket spark plugs that we get here do not have a coating on the threads. If there is a coating on the threads of the spark plugs you buy, then anti-seize is not required.

Your Answer:


Looking for a Used Trailblazer in your area?

CarGurus has 29 nationwide Trailblazer listings starting at $2,950.

Postal Code:

Chevrolet Trailblazer Experts

  • #1
  • #2
    G A Arne
  • #3
View All

Find great deals from top-rated dealers


Related Models For Sale

Used Chevrolet Tahoe
8 Great Deals out of 691 listings starting at $6,995
Used Chevrolet Blazer
4 Great Deals out of 1,192 listings starting at $4,790
Used Jeep Grand Cherokee
91 Great Deals out of 4,719 listings starting at $1,938
Used GMC Envoy
17 listings starting at $5,995
Used Chevrolet Silverado 1500
118 Great Deals out of 10,134 listings starting at $3,655
Used Ford Explorer
44 Great Deals out of 2,973 listings starting at $4,999
Used GMC Yukon
14 Great Deals out of 929 listings starting at $3,900
Used Chevrolet Impala
16 Great Deals out of 888 listings starting at $2,495
Used Ford F-150
177 Great Deals out of 12,353 listings starting at $3,300

Used Cars for Sale

2009 Chevrolet Trailblazer For Sale
2 listings starting at $7,950
2008 Chevrolet Trailblazer For Sale
6 listings starting at $3,850
2007 Chevrolet Trailblazer For Sale
5 listings starting at $2,950

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use. Content will be removed if CarGurus becomes aware that it violates our policies.