What to look for in a rough idle engine?
What to look for in a rough idle engine? Remove the spark plug to inspect it. Check the condition of the plug tip. Look for signs of contamination like oil (which may indicate worn rings, a scored cylinder or leaking valves), ash (poor fuel or oil leak), carbon (weak ignition, rich mixture), damage (perhaps from preignition or use of a wrong plug for your model). How often should I replace my spark plugs? And remember to replace your spark plugs at the manufacturer's recommended interval. Spark plug wires can also be the source of a rough idle. Many vehicle manufacturers...