changing spark plugs and wire advice
JK Newbie
Joined: Aug 2011
Posts: 19
Likes: 0
From: Ankeny, Iowa
I'm at 47,000 miles. I have superchip 87 oct tune running 89 gas (10% ethonol here in iowa) . Thought it was running a little (slightly) rough so decided to try plugs. I put in E3 plugs despite contraversy in forum. I think they improved drivability. Runs smooth. Accelerates smooth. Holds speed. Very happy. Hope they hold up well.
JK Freak
Joined: Apr 2011
Posts: 847
Likes: 0
From: Texas
give the plug wires a twist in both directions before pulling them off .
Performance Distributors Scream'n Demon + livewires makes a difference. Really notice it with SuperChips 91 tune.
I'm running 91 tune until I get regear done, more at the pump yes, but my mileage gain makes it cheaper per mile than 87. I do a lot of city/freeway driving.
Also have aFe CAI and will be putting on exhaust as soon as I get time and this damn Texas heat goes away - missed the cool window last week.
Performance Distributors Scream'n Demon + livewires makes a difference. Really notice it with SuperChips 91 tune.
I'm running 91 tune until I get regear done, more at the pump yes, but my mileage gain makes it cheaper per mile than 87. I do a lot of city/freeway driving.
Also have aFe CAI and will be putting on exhaust as soon as I get time and this damn Texas heat goes away - missed the cool window last week.
JK Newbie
Joined: Sep 2011
Posts: 6
Likes: 0
From: Eden, North Carolina
Okay, for those of you that have changed plugs, are you seeing any difference in MPG? I have read the threads and opinion is many different plugs used, Champion, Bosch, NGK, etc, but is there a difference other than smoother running, betetr idle? Appreciate any info, just bought my '07 several weeks ago and want to start my personal maintenance routine since I do not know what was previously done. Owned many Jeeps in the past, as always, regretted selling some, but this one I plan to keep for awhile. Info please 
. Thanks
. Thanks
JK Freak
Joined: Aug 2010
Posts: 722
Likes: 0
From: Miami, Fl
I'm at 47,000 miles. I have superchip 87 oct tune running 89 gas (10% ethonol here in iowa) . Thought it was running a little (slightly) rough so decided to try plugs. I put in E3 plugs despite contraversy in forum. I think they improved drivability. Runs smooth. Accelerates smooth. Holds speed. Very happy. Hope they hold up well.
Welcome to the Forum.
JK Newbie
Joined: Oct 2011
Posts: 34
Likes: 0
From: Alberta
I've had horrible luck with my jeep, both fixing and mpg,
After replacing:
Spark plugs
Alternator
Starter
oil change
fluid flush
diff oils
Clutch assembly
bearing
Rotor
all break pads
Caliper
power steering pump
an alignment
and finally 10 wheel studs (this all a few months from the dealership, was second hand)
I still sit at 15.5 mpg in the city and 17 mpg on highway
6k$ into this thing and its sat for 4 months in total, but everything replaced now and I can finally get to have some fun out of it.
Plugs were just done at 152K...
After replacing:
Spark plugs
Alternator
Starter
oil change
fluid flush
diff oils
Clutch assembly
bearing
Rotor
all break pads
Caliper
power steering pump
an alignment
and finally 10 wheel studs (this all a few months from the dealership, was second hand)
I still sit at 15.5 mpg in the city and 17 mpg on highway
6k$ into this thing and its sat for 4 months in total, but everything replaced now and I can finally get to have some fun out of it.
Plugs were just done at 152K...
JK Junkie
Joined: Jan 2011
Posts: 3,817
Likes: 4
From: Covington, LA
Originally Posted by Fonly
I've had horrible luck with my jeep, both fixing and mpg,
After replacing:
Spark plugs
Alternator
Starter
oil change
fluid flush
diff oils
Clutch assembly
bearing
Rotor
all break pads
Caliper
power steering pump
an alignment
and finally 10 wheel studs (this all a few months from the dealership, was second hand)
I still sit at 15.5 mpg in the city and 17 mpg on highway
6k$ into this thing and its sat for 4 months in total, but everything replaced now and I can finally get to have some fun out of it.
After replacing:
Spark plugs
Alternator
Starter
oil change
fluid flush
diff oils
Clutch assembly
bearing
Rotor
all break pads
Caliper
power steering pump
an alignment
and finally 10 wheel studs (this all a few months from the dealership, was second hand)
I still sit at 15.5 mpg in the city and 17 mpg on highway
6k$ into this thing and its sat for 4 months in total, but everything replaced now and I can finally get to have some fun out of it.
JK Junkie
Joined: Apr 2010
Posts: 2,123
Likes: 1
From: - - Jeep-topia - -
With 152k on the clock, that seems reasonable.
I didn't see transmission, engine, axle, t-case, etc. In that list. I would hope for the same, longevity like that. Nice job keeping your JK alive!
I didn't see transmission, engine, axle, t-case, etc. In that list. I would hope for the same, longevity like that. Nice job keeping your JK alive!
JK Enthusiast
Joined: May 2011
Posts: 428
Likes: 1
From: Memphis
Screamin demon coil pack
Granelli plug wires
NGK g platinum plugs capped to 0.65
I have a 2007 JK unlimited X with stock gears. 2 1/2" lift & 35" tires & no engine mods. I've driven everyday for the last month, over 1000 miles. I've filled up 3 times & averaging 17.3 mpg. On the interstate at 70 mph I'm turning around 1900 rpm & getting between 19 & 20 mpg. At 60 about 1600 rpm between 18 & 19. Definitely running smoother & more throttle response. Definitely a great improvement on the engine overall performance over mpg.
Granelli plug wires
NGK g platinum plugs capped to 0.65
I have a 2007 JK unlimited X with stock gears. 2 1/2" lift & 35" tires & no engine mods. I've driven everyday for the last month, over 1000 miles. I've filled up 3 times & averaging 17.3 mpg. On the interstate at 70 mph I'm turning around 1900 rpm & getting between 19 & 20 mpg. At 60 about 1600 rpm between 18 & 19. Definitely running smoother & more throttle response. Definitely a great improvement on the engine overall performance over mpg.