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Overheated Saab

I have a 99 Saab 95 SE with 118,000 miles on it. I have had 2 separate incidences where the car has overheated in heavy commuter traffice. The temp needle never goes above the middle so I can’t tell it’s overheating until I stop the car and it is spewing hot antifreeze all of the ground out of the overflow container. I am not driving the car until I find a good Saab mechanic to look at it. I haven’t had the car very long and want to take it to a good reputable mechanic.

Odd that the needle isn’t getting all the way into the red, especially if things are getting hot enough for coolant to spew from the reservoir. Can you tell if the coolant is actually boiling, or is it simply leaking out?

Any chance the problem is actually a faulty radiator cap that’s not venting under pressure?

I believe that it is boiling, based on the fact that it is escaping the overflow container under great pressure, and there is a lot of steam. Interestingly enough, I have not been able to find an actual radiator cap, only the cap for the overlow. One thought that I had was a stuck thermostat.

That is a possibility but when you stop the car heat and pressure can build up so it may be as simple as a faulty overflow cap that does not perform to specs. Check that first.

I will do that…thanks for the great feedback

Have you verified that the radiator cooling fan cycles on when the engine reaches a certain temperature and that both fans cycle on when the A/C is on?

It’s quite possible for the temp gauge to show a normal reading if the coolant level is low so that should be taken into consideration.
(This is caused by the lack of hot coolant flowing over the temperature sender probe.)

Thermostats should be changed every 3-4 years, bad or not. They’re cheap insurance against an engine roasting and they can act up one minute and be fine the next. The cap on the coolant bottle is the only one present on the car. Hope that helps.