I checked all plugs and wires on my 2000 dodge dakota... they are perfect,cap and button were fried so I replaced them. No improvement. When pulling a plug looking for spark, the truck started and ran with no applied gas, but when the plug was put back in, had to apply gas to get it to start.I thought that was kind of backwards.coil is fine. Don't know what to look for next.any help would be great

Hi, Someone with more knowledge than me my have a better answer, but if it just does this on one plug I'd look at it as being bad, just because it looks good doesn't always mean it is good.