Check Engine light on 1999 rodeo

My check engine light has been on for about a year now. I went to go to a diagnostic check on it, and the code said it was an "evap" leak, but when they tested it with smoke, no leaks were found. I replaced my gas cap, and that seemed to fix the problem temparily. About a month ago, the check engine light kept coming on and off 3 or 4 times, and now it is stuck on, with a brand new gas cap and a diagnostic check done twice on it. Any one have any idea how I can fix it? My inspection is due in a month and I got some trips to make in the summer with my truck and a trailer with my motorcycle. Thanks people.

have you ever had the intake manifold gasket replaced?

That is a bit strange, I read about GM having a large recall on the intake manifold gaskets. I am going to see if i can replace that myself in my garage.

Here is lots of info on replacing the IMG (thanks to Amigo-2k's FAQ)

http://isuzufaq.ibctech.ca/#faq5

Just remember the revised torque spec is 13 ft lbs. Use an inch lb torque wrench though since at that low setting the ft lb one will be very innacurate.

Thanks Gizmo. I'm gonna have to pick a lb per inch torque wrench tho, I only have the large.