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Old Aug 28, 2009 | 01:51 AM
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Default Over heating

For the past few months my car has been over heating alot. I replaced the water pump maybe 6 months ago and it kept on over heating. I brought this issue to Auto Zone and they told me I should change out the therm stat, which worked good for alittle bit. Then the past few days its been getting pretty hot and my low coolany light would come on. To check the coolant I would wait until it was cold and it was full.

Tonight I did about a 100 miles drive back up to school and it stuck at 180 degress the entire time but the last few miles my low coolany light went on and the temp rose quickly. I parked the car in my apartment complax and looked under the hood and under the car and there was no leaking coolant. I have talked with a few people and they think my cats could be bad? What do you guys think?

I also had a friend tell me when I got to her place that my car was really bad smelling and my temp gauge was reading about 220
If it helps at all, these were my smog number from a month ago

At 15 mph: PASSED
%CO2 Meas = 14.53
%O2 Meas = 0.29
HC (PPM) MAX 51, AVE: 9, MEAS 12
CO (%) MAX: 0.48 , AVE: 0.02, MEAS 0.05
NO (PPM) MAX 419, AVE 57, MEAS 418

At 25 mph: PASSED
%CO2 meas = 14.50
%O2 meas = 0.21
HC (PPM) MAX 35, AVE: 7, MEAS 11
CO (%) MAX: .46, AVE: 0.03, MEAS 0.04
NO (PPM) MAX 706, AVE 50, MEAS 394

Last edited by uLs1a; Aug 28, 2009 at 01:57 AM.
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Old Aug 28, 2009 | 05:18 AM
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Is there fluid in the coolant overflow tank? Sounds like an air pocket in the cooling system. If no or if low coolant level in the overflow tank, then add water to the tank & run the heater on high with the car @ temperature for 10 minutes or so to help purge the air.

Have you removed the corssover tubes on top of the heads?
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Old Aug 28, 2009 | 03:24 PM
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Yeah everything is full. I took off the coolant crossover pipes back in february
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Old Aug 28, 2009 | 03:27 PM
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sounds like an air pocket. No u'r cats dont have Anything to do with that. those people are fools. if u passed emissions u'r cats arent bad. thats proof
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Old Aug 28, 2009 | 04:56 PM
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He had to test the car twice for it to pass. The first time he put it on the machine, my car failed. He then let it run a few minutes and tried again and I passed with those numbers above
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Old Aug 28, 2009 | 05:00 PM
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Try popping off the radiator cap, start the car, and let it get to operating temp. This will insure your system is full when the coolant is circulating. When you check it cold, your radiator may be full, but the block could be low. Also this will allow you to evacuate any air in the system.
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Old Sep 2, 2009 | 04:18 PM
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Alright so I have driven around with the head on for a few miles and I have started the car cold with the radiator cap off and filled it up as it got warmer.

Today I drove back home to San Diego which is 105 miles and all th way down the freeway my car ran at about 190 -210 and once I got off the freeway the temp quickly rose up to 260. Im gonna swap the swap pump tonight and put a new thermo on it. The cap for my overflow tank (under the battery) whenever I get done driving the car is always wet and it looks like coolant is spilling over, is this normal or should I get a new cap for it? Anyone have any other ideas?
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Old Sep 5, 2009 | 11:52 AM
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Is the air dam under your car in place and not broke. Also are your radiator fans coming on. Both of these issues will cause you to heat up. Is the carpet wet on the passenger side of your ride or does the windshield fog up when you start the car. both could be a heater core leak. Your A/C could also cause heating up if it's working really hard. How does your car run without the A/C on. just some thoughts, good luck.
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Old Sep 8, 2009 | 09:46 PM
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you have a leak somewhere in your cooling system...

test the cooling system with the engine off...see if it will hold pressure for two minutes... if it does then test the cap...from what you described, it seems as if the radiator cap is the culprit of the overheating, but always test to confirm...

in your other thread you mentioned milky coolant, and reasons you believe a head gasket needed to be replaced... compression test/leakdown will help determine what cylinder/s are leaking...plus if your car is consuming coolant, theres a good chance youll know exactly which bank its from when you pull the spark plugs...if you find the head gasket needs to be replaced, fix it before you try to test the cooling system...
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Old Sep 9, 2009 | 12:29 AM
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Buy a new radiator cap man. You're losing pressure into the overflow tank while driving which means you have air in there. Air in place of coolant means higher temps. When you get off the highway you lose that nice ram air cooling from the air dam so it gets hot, the fans are nowhere as good as the ram air. Then the coolant goes back into the radiator as it cools and it looks like the level is good when you check it later. Its also why the low coolant light comes on while driving, you're low at that time.

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