Corvette Emma
Well-known member
Once in a while while driving, the low coolant message pops up but the coolant level is actually fine.
Has anybody else encountered this problem?
Has anybody else encountered this problem?
Low Coolant Message
- Thread starter Corvette Emma
- Start date
Sounds like you've got an air pocket in the coolant system somewhere. Start your car cold and let it warm up to whenever the Tstat opens to, then rev it to 1500 or so and fill the radiator and let it run at that RPM for a minute to circulate through the whole system, then you should have gotten all of your air pockets out of the system.
Emma, with your car cold, check the fluid level of your coolant reservoir to make sure it's within spec. There should still be coolant in there, since the system draws in coolant while the car is off and cooling and lets it out again when it's hot and running.
Then, with your car cold (never remove the cap when the car is hot), remove your radiator cap and start your car, and let the car come to normal operating temperature while observing the coolant level in the radiator. It's pretty easy to see if the coolant level actually falls below the level of the sensor.
If the coolant level doesn't change in your reservoir, you may have a leak somewhere, check your garage floor. Sometimes the car can develop tiny coolant leaks that quickly evaporate, these are hard to find. It might also be the heater core, the one on my 89 just started leaking one day, there was a strong smell of coolant inside the car and there was coolant dripping onto the passenger side carpet. You might also check your oil, if there is a head gasket leak the oil may look lighter than the dark chocolate color it's supposed to be.
Then, with your car cold (never remove the cap when the car is hot), remove your radiator cap and start your car, and let the car come to normal operating temperature while observing the coolant level in the radiator. It's pretty easy to see if the coolant level actually falls below the level of the sensor.
If the coolant level doesn't change in your reservoir, you may have a leak somewhere, check your garage floor. Sometimes the car can develop tiny coolant leaks that quickly evaporate, these are hard to find. It might also be the heater core, the one on my 89 just started leaking one day, there was a strong smell of coolant inside the car and there was coolant dripping onto the passenger side carpet. You might also check your oil, if there is a head gasket leak the oil may look lighter than the dark chocolate color it's supposed to be.
- Thread starter
- #4
Corvette Emma
Well-known member
tyrel said:
Hey Tyler,
I'm bored in Maryland so I went out to do what you said with the following results.
I started the car with the rad cap off. The coolant level in the rad dropped down about an inch, as the car began to warm the coolant started to rise. The coolant reached the top and ran over before the therm had a chance to open so I had to shut it down and put the cap on.
What do I do now? I am so confused???????
Lee
jmccloud
Well-known member
Low coolant
Your experience in operating with the radiator cap off is normal (burping). If your Corvette isn't loosing antifreeze (no puddles underneath and no need to add to keep the levels up), your difficulty is probably in the black high pressure reservoir tank just behind the right front tire. The low coolant sensor is in this high pressure tank. A lot of crud tends to collect in that tank and can interfere with the sensor's operation (I think it's just a float but never actually saw one).
When your car is cool, take the high pressure lid off of that high pressure tank (not the overflow tank in front of the wheel and not the radiator) and syphon out the fluid and flush it several times - just the fluid in that black tank. Top it off before returning the pressure cap. Running without this cap or the radiator cap will cause fluid to burp out as the car heats up.
If this doesn't work, you may need a new sensor.
Another possibility is a bad pressure cap on the black tank. If it permits air out (like it's supposed to) but also permits air in, the black tank will run low. If you buy a new cap, check the owners manual and avoid going to too high a pressure. LT1's only use a 15LB cap.
All this assumes that you have no leaks and have no need to add fluid to maintain level.
My Corvette is a '95 so there may be some differences.
Hope this helps
Your experience in operating with the radiator cap off is normal (burping). If your Corvette isn't loosing antifreeze (no puddles underneath and no need to add to keep the levels up), your difficulty is probably in the black high pressure reservoir tank just behind the right front tire. The low coolant sensor is in this high pressure tank. A lot of crud tends to collect in that tank and can interfere with the sensor's operation (I think it's just a float but never actually saw one).
When your car is cool, take the high pressure lid off of that high pressure tank (not the overflow tank in front of the wheel and not the radiator) and syphon out the fluid and flush it several times - just the fluid in that black tank. Top it off before returning the pressure cap. Running without this cap or the radiator cap will cause fluid to burp out as the car heats up.
If this doesn't work, you may need a new sensor.
Another possibility is a bad pressure cap on the black tank. If it permits air out (like it's supposed to) but also permits air in, the black tank will run low. If you buy a new cap, check the owners manual and avoid going to too high a pressure. LT1's only use a 15LB cap.
All this assumes that you have no leaks and have no need to add fluid to maintain level.
My Corvette is a '95 so there may be some differences.
Hope this helps
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