1999 volvo s70 overheating

you probably have your finger on the problem. have oil pressure test .when engine hot minimum 12psi.and change the thermostat.Don't cost much

Subarus can be challenging to "burp" Sometimes it takes several attempts to get the air out of the system. The procedure is simple. Top off the radiator, squeeze the hose a few times to help get the air out, replace the cap and start the car. let it idle or drive slowly near home with the heat on high. once the temp gauge begins to rise, if there is no heat get the car back to the driveway before the temp gauge gets half way. Shut the engine off wait for it to cool, at least 10 minutes. Then check the radiator again. If there is still air top off again and repeat. After 3 or 4 attempts if there is still air and or the coolant reservoir seems to be filling, try replacing the radiator cap. If this doesn't solve the problem, It may be a head gasket.

Sounds Like A Problem With your thermostat. Good Luck

the first thing to do is fit a new thermostat.cos if stuck open,the water temp WILL go down when cruising.

first i would purchase a new radiator cap 15 lbs 16 lb capacity cost about $7..then you must let car cool completely...now check radiator coolant level.. top off if it needs it. Now install new cap..let car warm up normally and after it get to normal temp range or higher put hand on upper radiator hose..it should feel hot and when you squeeze it you should feel a slight back pressure..this will mean that the thermostat and water pump are working correctly. if not either the thermostat you purchased is defective or your pump may not be working properly.
when you use just water in an engine the boiling point becomes 212 when you add the correct amount of antifreeze, depending on where you live, the boiling point will go up to 240 degrees. Make sure you put in the correct amount of mix.50/50 will usually work well. sometimes when a gauge does max out like that it could just be trapped air. if after you checked all this out and no air is trapped in the system, i would think that you may have a bad temp sensor. let me know if this helped thanks.

something is strange here thats for sure ,firstly take thermostat out and put it in a saucepan of water and boil it to see if opens .,check the oil light switch and pull the rubber boot cover back to see if any oil is behind it ??.-You are buying trouble with a car with such a high mileage on it ,never buy anything with more than 50,000 miles or you are just buying someones rubbish

I had problem with overheating on motorway when I drove over 60 mph i changed thermostat,radiator,thermostat housing, nothing helps.Then i find out that the problem was AIR IN THE COOLING SYSTEM try to squeeze all rubber pipes especially where is coming coolant to radiator.

That sounds like a thermostat. Usually not an expensive problem, but one you want to address soon. Right now, it's convinced that the engine is hot, and is wide open. It could easily flip to thinking that the engine is cold and stick closed. THEN your radiator WILL boil over.

your thermostat probably stuck closed.when you cooled it down,it opened again.change the thermostat.

These models had a problem with the electronic control modules, and this is what controls the idle speed. Sometimes they just need to be cleaned, but sometimes they are defective. Volvo has extended the warranty on some of them to 10 years or 200,000 miles if it is found to be defective.

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