Discussion in 'KJ General Discussion' started by hueyflyer, Aug 9, 2005.
Hi Folks, any idea why Jeep wants the KJ 3.7l plugs changed at 30k? My OTHER car recommends 100k!
Unfortunately, they use a non-platinum spark plug that only has a life expectancy of 30k. Given the slight degree of difiiculty in replacing the spark plugs, I'd recommend platinums at the next replacement interval....I used some Bosch Platinum's in my wife's '02 Jeep Liberty Sport 4x4 w/3.7L. Spark plugs are a thing of the past for me now, however.....the '05 is spark plug-free.
yeah, I mine sure didn't last long after 30k if I recall correctly, either.
Changed mine out at 28k and they were worn out. Next time I think I will go more like 20-25k. If they where platinum plugs and you left them in for a 100k you may never get them out, especially w/ an aluminum head.
They are not too diffcult to change. Just make sure you have a long extension.
Sound to me like the platinum plugs are the way to go. Anyone have a brand recommendation. I have had very good luck with Champion Plats in other cars.
Geez... I better change my plugs I'm at 40k with the original plugs in yet.
Me to!! nono.gif
Did you say that the Jeep Liberty 2005 doesn't have spark plugs ("the '05 is spark plug-free")? Otherwise, its just my misunderstanding. Thanks ...
His 2005 has a diesel engine, which does not use spark plugs.
Concerning platnums- My experience is that they can potentially degrade the performance of engines designed around copper plugs. They certainly will not increase performance. At best, they will not degrade performance
The only reason platnums exsist is so the marketing department can say "100,000 miles between tune-ups". But that isn't even a good trade off! 100,000 miles is a "schedual A" type number. If you use your KJ like a jeep was designed, You are likely a "schedual B" driver! Platnums should be done more like 50,000 to 60,000 miles. So if the platnum plug is twice the price, you are only breaking even, and there is no benefit!
I'd suggest moving to a better brand of copper- NGK or Bosch. forget Champion & Autolite even exist![/quote]
I was thinking the same thing. Its a crd though.
NGK is what ill use when the time comes around.
Wowsers Bennett. Definitely change those puppies. I spaced out and didn't change my wife's plugs in her PT Cruiser until 44K. They were gone daddyo! BTW...changing plugs in a Cruiser is kinda a pain too. Gotta disconnect the throttle cables and remove the intake manifold. jeez!
I just changed mine for the first time at about 55k. I measured the gap on all the used ones and they were all worn down the same amount (consistency is good!?) to .08, double the distance of .04 for the new ones. I never had a misfire etc. with the old plugs bc of the large gap however there may have been some irregular fuel burning in the cylinders that I couldnt hear. I didn't see any change in mileage w/ the new plugs.
Yeah I just took my 2002 sport in for a tranny drain/flush/filter replacement, transfer case drain and fill, and replaced my 47k mile spark plugs. ( when I bought my jeep she had 35k miles ) 5 of the 6 plug's electrodes were burned down to the porcelin. When I got her back I noticed a huge change in repsonsiveness, and about a 2 mpg difference. After it was all said and done my local garage charged me $139 which included the filter, and the platinum champions.
Just did the change today on my '04 with 20,624 miles. I bought the Bosch Platinum plugs. Took me about 1.5 hrs to complete the whole process, but honestly felt like 45 minutes. To me the job was very easy!
I know that I may have done it a bit early for some, but I didn't want to wait for P030X codes. lol3.gif It did seem to be running a bit rough in lower RPMs. I haven't driven it yet to see if that solved it though.
Fresh oil, fresh air filter, fresh plugs! All in one day.
I'd investigate the throttle body; chances are it could be your culprit. A little throttle body cleaner and an old tooth brush will do wonders !
Separate names with a comma.