first off, the fan must get REALLY HOT before it kicks on. if it will not come on at all ?, this either means the fan control unit is bad ?, or the oil temp sensor is bad ?. or...the fan itself is bad ?. you can test the fan by hooking a 12 volt battery straight to the fan to see if it runs ?. as for the oil light coming on, then going off ?, this is how they work. as for the c.d.i. where did you buy a c.d.i. for it ?, as they are discontinued today, so this tells me you got it from ebay or amazon, and both are chINA junk for one, and for two, most sellers have no clue what they are selling you, cuz they will '' claim '' it works on all years from '86-'89...AND THEY DON'T !. '' most '' trx350D's won't fire the spark plug if the fan control stops working. sooo..you need to sort out the fan control first before you go chasing a spark issue. hopefully you still have the old c.d.i. that you removed from it ?.