Hey everyone, don't hate me for posting before searching but i really need some help here, (I will search after i post, probably all night). Anyway I was driving from SLC, UT to Boise, ID and a couple hours into the drive the engine started acting strange. The best way for me to explain it is, on old 2 cycle engines when you start them cold, if you give WOT at first the engine just boggs down and won't go. That is exactly what is happening, if i put the gas pedal to the floor the engine just boggs down and slows me down immediately. Sometimes it is only at full throttle, and sometimes it is half to full throttle. After a while of driving the CEL turns on and then the engine runs perfectly normal. Then after a while again the CEL will turn off and the engine will start acting up again. So in the end i did make it to boise, but i do need to get back to slc this weekend. So I need help on a few things, first there is no ODBII port on my rodeo, so if anyone has the information on how to get the CEL code that would help a lot. Second has anyone had this problem before or have an idea of what it is? Oh one more thing that might help diagnose the problem, whenever it boggs down i see dark black exhast coming out the exhast pipe.

Any help would be greatly appreciated!
Thanks!