cooling problem

Car does fine as long as it is moving but if you stop and let it idle it starts to warm up. At about 3/4 on the temp gauge the fan kicks in and cools it right down. Checked the temps with a RayTec gun and after just 2-3 mins it will not exchange any temp across the rad. Starts out exchanging about 10 degrees then drops to about 2 degrees. Acts like the cooling system is blocked or the pump not doing it's job. The anti-freeze has been changed on a regular basis and it has a new factory thermostat which made no difference. New belt and it is not slipping. Does not get rid of any coolant or cause any other problems, but even at 20 degrees the temp will climb enough to turn the fan on in 2-3 minutes. Don't think it should do that. Thanks for any help!

with the engine off and cold disconnect the deaerition line(small hose from the intake manifoid to the top of the resivoir)route the line into the resivior so you can see it but it won't make a mess. withe the engine running coolant should flow from the intake manifold to the resivor via this hose. if it doesn't i would remove and inspect the water pump, all hoses(there are 7 total), and maybe what little of the block passiges you can. if coolant does flow, i'd double check that thermostat. does the heater work?

if it goes up to the 3/4 mark and goes down its normal. if it goes above that then there is an issue. saturns temp gauge is slightly different from most gms, where the gauge would go between the 1/2 and 3/4 mark and the fans kick in, but saturns can go up to the 3/4 mark then kick in. at that range the temperature is like 220, just like the same as most every car.

but if the temperature seems to creep up there quickly, look into flushing the system, replacing thermostat, and maybe a bad water pump also it could be a bad pressure cap. it could leak out pressure causing it to heat up quicker. but if it climbs up there in steps, taking a bit around 3-5 mins on a hot day, then its fine. on a colder day of course its going to take a bit longer.

also is your car an automatic? if so it could be your transmission causing it to heat up quickly. a clogged transmission cooler line, bad fluid, not enough fluid, bad torque converter, and it can be many issues with a transmission that can cause issues too, since the transmission is cooled through the radiator.

with the engine off and cold disconnect the deaerition line(small hose from the intake manifoid to the top of the resivoir)route the line into the resivior so you can see it but it won't make a mess. withe the engine running coolant should flow from the intake manifold to the resivor via this hose. if it doesn't i would remove and inspect the water pump, all hoses(there are 7 total), and maybe what little of the block passiges you can. if coolant does flow, i'd double check that thermostat. does the heater work?

Had very good flow out of the deaerition line and installed a new pressure cap, no help at all. Leaning towards replacing the water pump now. What do you think?? Thanks for the help............Bob

yeah it could be the water pump, but it could also be the transmission if its an automatic. if the transmission is having issues it can raise the temperature and cause the coolant to heat up quicker. my moms oldsmobile does that because of a bad torque converter, im just going to install a b&m cooler/fan because she doesnt want to get into the bigger job.