Hey
I have a 87 4 runner with a 4 cyl in it. Seems to be getting bad gas mileage and the tail pipe is black. Smelling unburned gas too.
Do I need to advance the timing more. I just don't want to have the engine idling too high.
Thanks

Check your computer for error codes.

Check your catalytic converter and make sure that it isn't breaking down. It happened to my 87 and it caused a performance drop. Have you noticed any flat spots or stumbling in the rpm band when accelerating? There are only 4 bolts holding the cat on and be careful when you do loosen it. If the material has broken down then you'll get coated with a powdery substance when it comes loose.

Thanks for the suggestion. I will check out the cat converter since timing adjustments are not doing much. I do get a gasoline smell though like it is burning way too rich.
How do you like the Kia?