I have a progressive deterioration of the idle running. At first I supected dirty plugs due to too much choke but I checked the spark when renewing the plugs and found something else. There would be a good spark for about 3 seconds and then cut out. Then a nother attempt to start would give no spark. Turning off the ignition and leaving it for 40 secobnds or more another attempt to start would produce a spark. Has anyone heard of this problem , I would hate to renew the CDI and then find out its to do with the timer on the fuel pump?)