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Had a miss fire code p0300

01saharatj

Member
Joined
Apr 16, 2019
Messages
29
Location
89031
So recommend action was to replace spark plugs ....check the pics and see what you think of the plugs i pulled out these were the worst ones

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A6D0B091-7CC5-410D-B527-B1D1D56076A5.jpeg
 

Jerry Bransford

TJ Guru Moderator
Staff Member
Supporting Member
Joined
Nov 9, 2015
Messages
25,464
Location
Fleming Island Florida
Jeez those are nearly as bad as I've ever seen. You have a "waste spark" ignition system which is fairly fussy about what plugs it will run well on.

Here are three good spark plugs that work well with waste-spark systems. Good for 100k miles, the Autolite APP-985 (not the AP-985!!) and Champion 7412. Both of those are double-tipped platinum which just means the platinum coating is on both sides of the gap. Good for 200K+ miles is the Autolite XP-985 which is an iridium plug. All three plugs use what's called fine-wire technology which means they will fire more reliably in tough combustion situations. You can't go wrong with any of those three.
 
OP
01saharatj

01saharatj

Member
Joined
Apr 16, 2019
Messages
29
Location
89031
Fyi these plugs and current coil pack were replaced in 2014 when i had to redo the head when i blew the head gasket