Here are my symptoms, starting the car in the mornings it likes to stall but after a few minutes it idles fine, when I step on the gas kinda hard it runs rich and throws out black smoke, I have no check engine light on and I did a diagnostic check at Auto Zone and came up code 67 which said something about the A/C being on which isn't possible because I removed the A/C. Note that I have 220,000 miles on this thing. And sometimes when I am going up a hill and it is in 4th gear(manual tranny) it seems to misfire sometimes. That could be a spark problem. So help me out guys I am confused on what I should do. Oh and my mods are off-road x-pipe and flowmaster mufflers. Any help will be greatly appreciated.