On my 93 I changed it, as I recall it was about a 14mm hex, brass, it is just centerline from the two firewall hoses and about 6" down from the top of the plastic head cover. I remember??? a two wire D shaped connector with a locking prong. I used a small plastic tube poked down the coolent res hose to syphon to below sensor level. Job took less than an hour, I think the sensor was close to $50 as I did not have time to shop.