Mysterious overheating - completely lost
09-21-2017
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Mysterious overheating - completely lost SO! First time I've ever been on a forum so I apologize in advance for any lapses in etiquette or anything.
97 civic ex coupe
Standard trans. CAI - only mod
206,000 miles
New: radiator, hoses, thermostat, 3 different caps, water pump has 60k on it.
Car ONLY overheats after highway driving for more than 20-30 miles. Begins to overheat when you come to a stop after Hwy driving. I can drive all over town in 110 degrees and the car will not warm up. Even parked and idling after running around town. Fans DO work and radiator fan cycles as does the condenser fan (not that that cools the coolant, I know). Fan seems to pull quite a bit of air through the radiator. I have bled the system on an extremely steep incline to the best of my ability. Head gasket tested good with the tester and chemical. Oil and water look fantastic with no debris in water either. I'M LOST!!! Lol! PLEASE HELP!
97 civic ex coupe
Standard trans. CAI - only mod
206,000 miles
New: radiator, hoses, thermostat, 3 different caps, water pump has 60k on it.
Car ONLY overheats after highway driving for more than 20-30 miles. Begins to overheat when you come to a stop after Hwy driving. I can drive all over town in 110 degrees and the car will not warm up. Even parked and idling after running around town. Fans DO work and radiator fan cycles as does the condenser fan (not that that cools the coolant, I know). Fan seems to pull quite a bit of air through the radiator. I have bled the system on an extremely steep incline to the best of my ability. Head gasket tested good with the tester and chemical. Oil and water look fantastic with no debris in water either. I'M LOST!!! Lol! PLEASE HELP!
09-21-2017
#2
If you think a good mechanic is expensive, try hiring a bad one
Re: Mysterious overheating - completely lost
Here's what I expect is happening while you drive:
Radiator level goes low. Reservoir level rises. Overheat happens after radiator goes low. These will overheat with less than a quart of liquid missing from the radiator.
Blown head gasket.
Radiator level goes low. Reservoir level rises. Overheat happens after radiator goes low. These will overheat with less than a quart of liquid missing from the radiator.
Blown head gasket.
09-21-2017
#3
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Wouldn't I notice an overheating issue while I drive? Especially with the raised heat and pressure? Granted, that's almost my only answer at this point but it's almost intermittent. And I drive 110 miles to and from work and no issues till I let it sit for a couple mins
09-21-2017
#5
If you think a good mechanic is expensive, try hiring a bad one
Re: Mysterious overheating - completely lost
Wouldn't I notice an overheating issue while I drive? Especially with the raised heat and pressure? Granted, that's almost my only answer at this point but it's almost intermittent. And I drive 110 miles to and from work and no issues till I let it sit for a couple mins
In the meantime, review everything in the first post of this thread, including the two videos:
https://www.civicforums.com/overheating-mysterious-coolant-loss-common-causes-reference.html
Also.....does it have good heater output?
Does it leak coolant?
Do you have to top off the radiator regularly?
Is the system fully burped?
Is the temp gauge accurate, and does it match ECT temperature value displayed on a scanner?
Are you sure the radiator fan runs when it should?
