1999 Chevrolet Astro LT 6 Cyl 4.30L
What is causing the knocking sound, black exhaust smoke, rough idle, and horrible gas mileage?
It has 179k miles, I recently changed the oil and plugs, there was no soot or il on the plugs. Last year it began to run hot due to a damaged radiator, but was running fine until late December/early January. It occurs all the time, especially at idle when the knocking is very loud. The check engine light has been on for a while., but I didn't know auto parts stores would read them. Also, I have a new distributor cap and will be getting plug wires and a rotor soon.