Takes forever to warm up

[sfoperat]

It seems that my 2000 silhouette takes forever to warm up now. When the temp gauge reaches the midway point, it drops back down to the 1/4 mark and you get warm air for awhile. Then it gets cold again until the cycle repeats. This goes on for quite some time until you drive around enough to get the engine good and warm. I changed the thermostat (192 degree model, same as spec) but doesn't seem to make a difference. Also, the coolant level is proper, but I did notice that it seems to "disappear" from time to time. I should probably just dump it.

[Milo2001]

Dissapear's from time to time? I would be a little concerned since the reputation with these v-6 engines of eating the intake manifold gasket. Check your oil dipstick for signs of coolant, also the outside of the engine.

When you changed the thermostat, did you purge the air out of the system. Typically what you do is get a funnel or the like and make a sealed fit on the radiator filler neck. Fill it up to the top with antifreeze/distilled water. Find the bleed screws and purge the air. Do it both with the engine off and running. There may be more bleed screws on the intake manifold, consult your manual.

Another thing to check to see if your radiator fans are constantly running.

Also I stay away from the $2.99 thermostats. Go to the dealer or find a higher quality one.

[macvhfan]

Originally Posted by sfoperat

It seems that my 2000 silhouette takes forever to warm up now. When the temp gauge reaches the midway point, it drops back down to the 1/4 mark and you get warm air for awhile. Then it gets cold again until the cycle repeats. This goes on for quite some time until you drive around enough to get the engine good and warm. I changed the thermostat (192 degree model, same as spec) but doesn't seem to make a difference. Also, the coolant level is proper, but I did notice that it seems to "disappear" from time to time. I should probably just dump it.

my 92 silhouette with the 3800 engine does the EXACT same thing...the fluid is disappearing on mine at times when the temp goes to the midway point.. at this same time you loose heat.. there must be a pressure release or something on the radiator just under where the air filter is located..... mine blows some fluid out here for a short time.. and then the temp will go back down.. and you get heat for a while !!!
i am going to try and flush heater core today?? i have a feeling thats not the problem though.. ( i also treid the thermostat too didnt help)
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