Sorry in advance for the long question:
My check engine light recently came on and am wondering why? I get 12 miles to the gallon ( after bringing to dealership for the emissions system cleaning ). How do I clean my erg valve? I am very unmechanical, is it something I can do? The tail pipe have a black powder on the inside ( assuming oil, not greasy though ). How do I change my pcv valve? HELP PLEASE!!! I travel 90 mile round trip and at this point it would be cheaper to take the helicopter to work! Thanks for all the help and appreciate it 120%!

http://kpaske.shacknet.nu/public/EGR.htm
http://www.geocities.com/endre_rl/isuzufaq.htm#faq1
http://www.icess.ucsb.edu/~greg/rodeo/egr.htm

these are links to Isuzu's not jeeps.

12 MPG in a Jeep sounds pretty good.

Best Bet..get a service repair manual (Chilton/ Haynes) from 'most any autoparts store. Read it ..Follow directions...If it's not in their, it's way beyond your capabilities. OR look for a local mechanic..ask friends for referals..I do not recomend dealerships..way too long to get your car back..you don't get to speak with a mech..and Way too expensive.
LOL

Best Bet..get a service repair manual (Chilton/ Haynes) from 'most any autoparts store. Read it ..Follow directions...If it's not in their, it's way beyond your capabilities.....
Have you seen the chiltons or haynes for a 1998+?? a complete joke :lol: (if you can even find one). Helms is the best way to go for newer zu's.
G/luck
Joel

My response stands..the ref to a Chilton/Haynes was meant to be generic..as opposed to buying an very expensive manf/dealer service manual, which they would obviously be lost in...this to a person who had NO idea what was going on. Therefore if they could not find their answer in a C/H book (etc) ....Get a Mech.