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My car wont reach the normal operating temperature.

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Old 03-29-08, 08:44 AM
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Och
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Default My car wont reach the normal operating temperature.

I am so frustrated I'm ready to drive this car off a cliff. Ever since I've replaced the water pump, The car wont reach the normal operating temperature. The temperature stays just a notch about the first line. I though my thermostat might have been deffective, so I just replaced it, and still the same thing.

Any ideas?
Old 03-29-08, 11:17 AM
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tbilisi79
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Does the heat work?
You should check the temperature at the thermostat housing using the laser reader. Could be your temp sensor.
Old 03-29-08, 11:29 AM
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Hey. The heat works. But even without testing the temperature with laser reader, I know its not reaching the point it needs to be at. I can open up the radiator cap at any time, not mater how long the car was running, and it doesn't do the "psss" that its suposed to do. Also, the coolant inside the reservoir isn't even warm.
Old 03-29-08, 12:46 PM
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its running cooler, which is usually better. i don't see the problem here...
Old 03-29-08, 12:49 PM
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that means u have a leak somewhere.

or its possible u have an air bubble in the lines.

when u filled the coolant, you did have the heater set to max hot and then let the engine run with the rad. cap off right?
Old 03-29-08, 12:50 PM
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Originally Posted by PureDrifter
that means u have a leak somewhere.

or its possible u have an air bubble in the lines.

when u filled the coolant, you did have the heater set to max hot and then let the engine run with the rad. cap off right?
i was thinking a leak, but wouldn't having a leak mean that its running hotter then normal?
Old 03-29-08, 12:53 PM
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Well a leak also can lower pressure. Pressure = more heat.

You sure your Rad. Cap is still providing the proper Psi?
Old 03-29-08, 01:05 PM
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not when unless ur running the motor for long periods of time while standing still.

sounds basically like the car doesnt have enough coolant, either due to a leak which is preventing pressure to build up, or the thermostat and heater valves werent open allowing air in and not filling up completely with coolant.
Old 03-29-08, 05:06 PM
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Hey guys... Ran it with cap and inlet housing open, with heat full blast. I don't understand whats happening. I don't see any antifreeze leaks, so I assume the pressure builds up. Although when I open the cap, it doesn't seem to release any pressure.
Old 03-29-08, 11:41 PM
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Originally Posted by Och
Hey guys... Ran it with cap and inlet housing open, with heat full blast. I don't understand whats happening. I don't see any antifreeze leaks, so I assume the pressure builds up. Although when I open the cap, it doesn't seem to release any pressure.
You might have a bubble in the system. Those are the common signs.
Old 03-30-08, 06:28 AM
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So whats my best way to get rid of the bubble? I've ran the car with radiator cap open for a long time.
Old 03-30-08, 07:34 AM
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Originally Posted by Och
So whats my best way to get rid of the bubble? I've ran the car with radiator cap open for a long time.
flush the system???
Old 03-30-08, 12:26 PM
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search the maint. forum, i recal a guy saying something about jacking up the front of the car as high as u can so the radiator is the highest point in the cooling system, then running it with the cap open so the air bubble will float to it.
Old 03-30-08, 01:51 PM
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Makes sense.. logical.

Though it should still go to full pressure even with an air bubble. But we aren't accurately measuring system pressure , we are just going by a 'sound' when the cap comes off =)

If it were me.. I would jack the car up -- I would flush the entire system.. I would put a hose to the inlet.. and put a bit of pressure in it. Nothing damaging.. just enough to get something running through -- Starting the car with 'just' water for a short period. Water alone wont' hurt it,.. (for short periods of time) -- IE: Don't let it warm all the way up. Also I wouldn't trust the temp gauge, so a minute or two at max here.

Refill,.. check all hoses,.. fittings,.. pump -- keep cap off.. and monitor temp -- get a temp meter,.. measure the fluid in the radiator ,.. see what its getting at. (how high)
Old 03-30-08, 02:07 PM
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it wont pressurize properly since the air bubble can compress, water, and pretty much every other room temp. liquid for all practical purposes does not compress.


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