2000 ox66 does not shutdown clean seems to diesel

[taf08172]

Motor seems to run fine but seems to diesel for several seconds when ignition is turned off. Kill lanyard does the same thing. I use Yamalube and Ringfee. Did the Seafoam shock treatment and had no change. Can an electronic fuel injection actually diesel? Any ideas?

 

[taf08172]

This problem started last season and i posted it on recollection. Actually the motor fails to stop for several seconds whether stopped by lanyard or ignition switch. It runs smoothly until it decides to stop normally. The time to stop varied from none to 5-6 seconds. I finally got past the logic of both of the stop contacts could not be bad. Got the meter out and both stop contacts were functioning but read 30k-100k when closed. New ignition switch panel and we are back to normal.