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'02 impala low-coolant light on but engine not hot?

I've had to add some water several times in the past six weeks to the overflow bottle. The low coolant lamp lights but the engine doesn't get hot (overheat)

7 Answers

  • 1 decade ago
    Favorite Answer

    First and simplest would be to replace the radiator cap. Sounds like it might be getting old and not holding pressure.

    The low coolant sensor is in the overflow bottle, hence the light is on but the engine is not overheating.

    Try to replace this low fluid with coolant and not just water. The straight water can freeze in the bottle cracking it and over time and refills will dilute the coolant in the motor/radiator.

    If you keep having to add coolant after the cap, you need to get the cooling system checked. It has to be going somewhere, lets hope a leaky hose, worst case a bad head gasket.

    Happy Holidays

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  • Evelyn
    Lv 4
    4 years ago

    I own a shop, and think you have a leak in the system some place. As for the light staying on a year, that sounds like a faulty sensor in the bottom of the recovery tank (where you add coolant), and it is either not floating up (stuck), or it is just no good. When adding coolant to your engine, you must keep in mind two things; One, the type of coolant you put into the system does matter, and only use the coolant the manufacture recommends or its equivalent. It should say right on the container "For all types of vehicles" if its the right one. Two; Pay attention to the marks where the level is to be filled to. Too much and it will throw it back out when the engine gets up to normal temperature. Coolant expands & contracts in the system, and if you don't leave enough room for it to expand, it will kick it out the overflow. If a system is allowed to get too low, it will pull air into it, and this air will have to be purged from the system, or it will cause hot spots, and an overheating condition. The best advice anyone could give you is to have it pressure tested along with the cap too. This way you will know right away what the problem is. There are many things that can cause this problem, and finding the cause can be difficult at times. The pressure test will find it 99% of the time. Have this done, and you will know what to do next. About the only thing a pressure test won't find is a sticking thermostat, so you may want to have that replaced anyway. Glad to help out, Good luck!!!

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  • 1 decade ago

    The lamp is on for one reason:

    1) YOU ARE LOW ON COOLANT!!!!! You've had to add to the system which means you have a leak somewhere.

    2) You keep adding just water, which is a cardinal no-no!!!! Only add coolant at a 50-50 mix. Plain water will eventually kill your engine dead. You wouldn't add just water to your corn flakes. never add just water or just coolant to your coolant system.

    Take your car to a reputable mechanic and determine why your vehicle is loosing coolant and get it repaired.

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  • 1 decade ago

    Check your water pump. Your water pump has 2 pilot holes just behind the pulley. If these holes are wet, your water pump is going bad. Sounds like you need to replace your water pump. Make sure you get the water-antifreeze mixture correct when you get your water pump changed. I had the same problem with my 02 GM. I replaced the water pump and have had NO problems since.

    Source(s): 16 years general maintenance
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  • 1 decade ago

    hthis cars have a habbit of airlocking just keep puting water in it when it gets low and it will be fine. unless you have cracked the head gasket. for this just check for water leaks around the head above the manafold and the smell of anafreeze.

    Source(s): experince
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  • 3DDD
    Lv 5
    1 decade ago

    Sounds like you have a leak. You can pressure test the system to find where. If you cant do it yourself it should not cost a lot for a honest mechanic to do it for you.

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  • Anonymous
    1 decade ago

    your sending unit is bad.change it.

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