I am the owner of a '99 Olds Alero 2.4. I purchased it a few monthes ago and been doing some routine mainatance. My new issue is with the temp gauge and the cooling fan operation. The temp gauge will creep up to between half and 3/4 line on the temp gauge(I do not know the temp but assuming around 210-220 degrees). At this point the cooling fans will turn on and the temp will drop to around a little under the half mark (the temp it is at while cruising) the temp gauge only climbs when sitting in traffic til the cooling fans kick on. My question for this would be is this normal if not do I have a bad sensor my relays are all fine and operating properly and yes I need a coolant flush as well (figured if I needed to replace something due it before I drain the coolant)?

Also one more question concerning the rocker box covers/valve covers do the come off with out haveing to messs with the cam or no?

 

I don't know about the 2.4l but I know the 3400's do the samething. If I'm driving in the city and stop at a light the gauge creeps up to about the middle of the half and 3/4 mark. When the gauge is sitting right at the half mark its 220*.

 

It creeps to half-3/4 marks then the fans kick on and drops it to the halfway I know the t-stat is 192* from the factory.

 

Well your gauge may not be accurate or the temp sensor needs replaced.

 

I know the G.M. gauges are off by 5 degrees +/- so I am thinking temp sensor. New question is where are they located?

 

Yeah! You should replace the temp sensor.

 

Its either a bad sensor or the thermostat. To test the thermostat remove it (follow your top radiator hose), boil a pot of water to 180 degrees and drop the thermostat in the water. It should quickly open up. if you live where its warm year around you can just remove the thermostat and drive without it. If you do remove the thermostat you will need a gasket and sealant to put it back on. Overheating at idle is 1 of the 2.

 

Its not all that easy to get to the t stat on the 2.4L. If your gonna go through the trouble to pull the t stat you might as well change the timing chain and water pump while your there.

 

Also one more question concerning the rocker box covers/valve covers do the come off with out haveing to messs with the cam or no?


No you don't have to mess with the cams to take the valve cover off.

 

I also think it is a problem of temp sensor.