Volkswagen: Testing/replacing thermostat, vw jetta, wire fan
Question1987 VW Jetta GLI-tends to run hot under normal driving conditions even during cool weather.
Answeri'm sorry to say that there are too many variables to give you a definitive answer. it may be a water pump or thermostat fault, a faulty fan switch, blocked radiator, clogged channels within the engine restricting water flow. also the fan may be warn and loosing effectiveness.
if you check the radiator is hot all over when the car is starting to warm up, then the chances are it may be a fan switch problem or fan problem. (if it is a three wire fan, it should work at two speeds, sometimes the slower first step doesn't work due to fan or switch) if the radiator doesn't get warm all over, then it may be blocked. sorry i can't really help anymore at this moment. if the above bit's appear ok, recontact me and i will try to offer more solutions.
