i have a car quest oil filter. my dad tells me outa all of his years of being a mechanic he thinks this is the best. u might ask "if ur dad is a mechanic then y dont u ask him about this problem" becuase my dad will start on the "i told yall not to modify this " and start raising hell. anyways i change it around 3000 miles . its probably been 2500 since we last changed it  

Unless you have a check engine light, a code reader is of no use. Change the plugs first. It's the cheapest and easiest thing to do. Then get rid of the spacer whith the spiral thingy in it. Thos espirals do nothing but restrict airflow. On the carb vehicles, it MIGHT help the fuel mix with the air, but since you engine is direct injected, all you are doing is creating turbulence in an area where engineers have worked long hours to make sure the airflow is smooth. Plus, you may have created a leak under the throttlebody.  

One more thing, listen to your dad. He is right, the less you mess with it, the fewer problems you will have. If you must change something, ask his advice first. If he says "bad idea" live with it. You both will be happier. Trust me, Im 41 and I've been down that road.  

thanks for ur input but i really have noticed a difference in the power i think that the heat restistant plastic helps with some heat. and i thought the air would combust better with the fins in it. this is the picture of the spacer. anything im understanding wrong

<a href="http://img409.imageshack.us/my.php?image=tbspacer1rd2.jpg" target="_blank"><img src="http://img409.imageshack.us/img409/6402/tbspacer1rd2.th.jpg" border="0" alt="Free Image Hosting at www.ImageShack.us" /></a>

Any power you have gained was probably from the low restriction airfilter you installed. there are several versions of that spinning thing on the market. None of which do anything than relieve your wallet of money. It's just a restriction to the flow of air, much like NASCAR restrictor plates. The spacer may or may not help without the metal spinning things. Every article I have read where one of these devices was tested has found a decrease in power. It's what they refer to as "snake oil". Airflow should be as smooth and straight as possible.  

i have a airaid poweraid on mine that i got for free,i have never seen one like what was in the pic,how that could help air flow is beyond me.i know the one i installed is boarder line worthless,the only thing that helped is when i had it and my throttlebody poked out to 62mm,thats when i noticed a differnce.and i still dont think that if i took it off i would notice anything differnt but noise.  

okay, alot of people say changign the plugs would be thing thing to do, but the jeep has about 70k on it and i changed the plugs on about 65k. COULD they possibly be bad, i think they are champion, like i said im in highschool and dont want to go spend 20 bucks on plugs when i have some brand new ones in right now  

buy 1 plug. put it in 1, if no better, put the one that came out of 1 into 2......

just make sure you got the correct plug wrench, or you'll bust the ceramic, and not save anything.

Spend the money on some good plugs. I have heard many complaints about Champion plugs going bad right after they are installed. Go with a high quality platinum tip plug. It will save you money in the long term.  

i think i figured out my problem, i found that carbon colects very fast becuase i cleaned it our not too long ago and it starts alot smoother. would anyone like to make a suggestion on wat kind of plugs they would get next time and does anyone agree or disagree with wat the guy said that they TB spacer only creates turblulence and does do anything for power and im guessing gas milage?

get some autolite single platium's,they run the best in a 4.0.i havnt had any problems and have always put them in my jeep motors.that particular tb spacer will restrict airflow,others do minimal gains,not really worth the money.get a bigger throttlebody,62mm,and you will notice a differnce  

So would it be best for me to ditch the tb spacer. People say that stock tb are tapered so you can bore them out a lil bit. Would that be worthwhile.  

yeah i would take it off.the tb itself is 62mm at the top and 58 at the bottom,all you have to do is have it machined out.or get one off ebay already done and send your core one back in.if you have the resources do it yourself.but you would notice the differnce right away with the bigger tb.  

how much difference am i gonna notice out of a bore job to the throtle body. in my small town there are 2 shops that could do it im pretty sure  it wont be expensive, but if u could tell me maybe a estimate guess on hp gains and im guessing it will help milage too?  and one more how can 4mm show me difference?  

going from 62mm to 66mm is a 13% increase in area. so maybe 5% hp? (wild guess) if you get 5% more hp thats 9hp