Pontiac Repair: Pontiac Grand Am Reaching high temperatures, intake manifold gasket, coolant temp

Question
Hi Todd, i own a 1999 Pontiac Grand Am GT 3.4 V6, i was wondering if you know when the fans are supposed to start. My car get to 90 Celsius Degrees (the center of the gauge) and stays there for a wile (10min) without fans coming on, then the gauge starts going up to almost 110 Celsius degrees, a little between the middle and the maximum temp, when this happens the fans start to work but in a very slowly speed, then the fans never turn off, the car does not overheats and the gauge comes down a little but the fans always stay on. Do you know what can be happening? i changed the relays and still the same, can this be caused by a defective coolant temp sensor?

Answer
Hi Hector:

usually the fans will come on between 220-225 degrees at low speed and if the temp continues to climb the fans come on at hi speed if they contiue to climb even more the service engine soon lamp will come on for and set an over temp code. sound like the fans are working right you have to do the math between F and C. and the temps I gave you are just ball park. The guage on the dash is never 100% exact either they rae more of in indicator mor then any thing else. to be 100% sure you need a true scan tool to read the engine data for temp and coolant fan operation. Make sure the coolant is full as well check it when the engine is cold. if it's low start looking for leaks. the lowrr intake manifold gasket and water pump is the first place to look for leaks. good luck :-)