running rich ? and fan switch

[srdtvr]

Just got my Chim MOT'd today but running rich. Tester said it maybe cold start or coolant sensor which is causing it to think its cold and dumping fuel in to compensate.
I suspect this has been a topic before but any ideas ?
Its an early 4 litre 1993

Also after fitting a new rad and otter switch - the fans dont kick in - I've got an overide switch but it would be nice if the switch worked. If I short out the wires the fans come on no problem - its the second otter switch as I thought the first one was faulty .

Cheers

[big geoff]

i would first of all remove 1 plug from each bank this will show if one side is rich than the other if one side is rich replace the lamba on that side .

[blitzracing]

Id go and get one of Steve heaths ECU mates, so you can measure the various sensors and see whats failed. You have too many options to guess otherwise.