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coolant light

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Old Apr 9, 2009 | 07:21 PM
  #1  
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coolant light

My coolant light sometimes comes on when im in 5th gear. My coolant is full though. Dealer said that it is because when I drive fast it the speed may push the liquid under the level.. does anyone else have this problem?
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Old Apr 9, 2009 | 08:17 PM
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Originally Posted by KINGShon
My coolant light sometimes comes on when im in 5th gear. My coolant is full though. Dealer said that it is because when I drive fast it the speed may push the liquid under the level.. does anyone else have this problem?
This is possible, but in a properly filled and operating coolant system it shouldnt happen. Add some 50/50 to the reservoir tank, maybe a tad overfull, and see if it helps, before that tho obviously check where the level of coolant is when it's cold (aka before you start it in the morning. It should be dead on or slightly above the full mark.

kevin.
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Old Apr 9, 2009 | 09:06 PM
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Be aware of the coolant level sensor going bad as myself and multiple others have experienced. Hopefully teknics' suggestion resolves the problem for you.
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Old Apr 9, 2009 | 09:13 PM
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the sensors are not so good. top it up though.
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Old Apr 9, 2009 | 09:39 PM
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yea the sensors are also known, but gotta aim for simple solutions first

kevin.
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Old Apr 9, 2009 | 10:07 PM
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Originally Posted by teknics
yea the sensors are also known, but gotta aim for simple solutions first

kevin.
If the simple solution works, that's great and also cheaper than that almost $200 (installation not included) @$%^& overpriced coolant reservoir which contains the sensor .

KINGShon - what's your car's year/mileage?
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Old Apr 9, 2009 | 10:11 PM
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This occurs with my car if I'm in a high RPM range (5000 - 7000) for an extended period of time. About a minute down the freeway..

Just double check the coolant level. when it's cold.
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Old Apr 9, 2009 | 10:18 PM
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Originally Posted by rx8cited
If the simple solution works, that's great and also cheaper than that almost $200 (installation not included) @$%^& overpriced coolant reservoir which contains the sensor .

KINGShon - what's your car's year/mileage?
well, there's always the black tape over the light DIY project.
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Old Apr 9, 2009 | 10:26 PM
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Originally Posted by rx8cited
If the simple solution works, that's great and also cheaper than that almost $200 (installation not included) @$%^& overpriced coolant reservoir which contains the sensor .

KINGShon - what's your car's year/mileage?
lol, i feel your pain man, believe me. Dealer is brutal with pricing on lots.

kevin.
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Old Apr 9, 2009 | 10:30 PM
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Originally Posted by myriadshalaks
well, there's always the black tape over the light DIY project.
Not such a brilliant idea when your water pump fails and you have zero notice because the bad coolant level sensor keeps the light always on. This happened to my car and I was checking the coolant level at least twice a month.
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Old Apr 9, 2009 | 10:37 PM
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Originally Posted by teknics
lol, i feel your pain man, believe me. Dealer is brutal with pricing on lots.

kevin.
I decided to change the water pump, thermostat, and coolant reservoir myself ...... any idea what a stealership would have charged?
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Old Apr 9, 2009 | 11:34 PM
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its an 05 with 25k miles on it
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Old Apr 10, 2009 | 03:49 AM
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let the dealer figure it out.

now to all the others with this issue../ 04 owners..

i have a hint..

pm. me.

it is a very obscure fix.

beers
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Old Apr 10, 2009 | 12:01 PM
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Originally Posted by rx8cited
I decided to change the water pump, thermostat, and coolant reservoir myself ...... any idea what a stealership would have charged?
a couple hundred dollars of labor, could probably figure out a decent estimate if you're really interested

kevin.
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Old Apr 10, 2009 | 03:48 PM
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Originally Posted by teknics
a couple hundred dollars of labor, could probably figure out a decent estimate if you're really interested

kevin.
I'd appreciate an estimate if you've got that time. TIA.
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Old May 10, 2009 | 12:44 AM
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i had this same issue...checked everything on a regular to make sure nothing was wrong..yea so last week when i checked out my car i noticed the coolant corrosion building under the water pump pulley..odd thing is it doesnt look fresh..and the light only comes on in 5th and higher speeds
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Old May 10, 2009 | 02:28 PM
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hmmm water pump failure is no joke, I think it's time for me to take a closer look!
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Old May 10, 2009 | 03:04 PM
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check coolant level....if not its a sensor probably
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Old May 12, 2009 | 12:41 PM
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yea i called the dealer and asked and they said that there is a coolant sensor that is really sensative and if it a teaspoon low it will come one...my issue is when i go to 6th the light goes away and the coolant level is fine...besides i did see the coolant residue on the bottom of the pump..
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Old May 12, 2009 | 12:49 PM
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04-06 8s have a faulty sensor that goes off when the sensor gets hot not the coolent. just pop it in to neutral and it will go off. invest in a digital water temp gauge for that it will help alot. or reaplace you coolent over flow tank cuz thats where the bad sensor is.
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Old Aug 4, 2010 | 08:40 PM
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coolant light

Okay, I've been reading all the threads and I am having the same stupid problem. Light goes on in high rev or if I'm going 80 for awhile (which is often). Yes, if I slow down or put my foot on the clutch, the light goes off. I also noticed that it doesn't happen as quickly when I don't have the air-conditioner on. Please don't call me stupid, but is the coolant for the engine connected to the coolant for the air-conditioner? Is changing the sensor the solution? What is an overflow tank? I hate going to the dealer and looking like a "dumb-chick" with a fast car. T in San Diego.
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Old Aug 4, 2010 | 09:57 PM
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safbud,
The sensor is built into the overflow tank (aka coolant reservoir) as shown in the attached image. The coolant reservoir holds engine coolant and is not related to the A/C, but is the source of heat for the car's heater.

First, make sure the coolant level is at the F mark when the engine is cool to make sure that is not the cause of the light coming on.

If the coolant level is fine, have the coolant reservoir (which includes the sensor) replaced. Ignore any stupid advice of just keeping any eye on the coolant level in place of having the repair done.

If your water pump ever fails, as mine did while my sensor was bad - you'll have zero notice that the car is losing coolant - which will cause the engine to overheat and possibly cause engine damage.
Attached Thumbnails coolant light-coolantreservoir.jpg  
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Old Sep 8, 2010 | 06:59 PM
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my 04 radiator light is constantly on and i put coolant about every 2 days. i also noticed some coolant ontop of the resevoir a couple time am thinking my cap could be loose?
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Old Sep 8, 2010 | 07:56 PM
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Originally Posted by 671rx8
my 04 radiator light is constantly on and i put coolant about every 2 days. i also noticed some coolant ontop of the resevoir a couple time am thinking my cap could be loose?
1.) Your coolant sensor is bad! It's a known issue. Only way to solve it is get a new bottle as the sensor is part of the bottle. Either that or you can simply unplug the sensor there to the left of the bottle and then you will have no light at all on the dash and you can then just monitor it and fill it when needed.

Now having said that..............let's discuss this coolant you are finding on top of the bottle and that fact you say you have to add some every couple of days.

When you say you are adding coolant every couple of days. How much are you filling it? You do know there is a full line on the side of the bottle and it's really not that far up on the bottle.........right? I have the feeling you may be overfilling it and getting leakage because of that. This could also be why you find some on top of the tank............but I've also seen cases where the top of the bottle was cracked and didn't allow for a good cap seal, but you can take off the cap(when cold) and inspect that.

Oh...............if you have been overfilling it, then stop! Because if you don't, it's going to drip down onto the power steering connectors, corrode them up, then you won't have power steering until you pull everything out and clean those connectors.




Attached Thumbnails coolant light-coolant_sensor_locale.jpg   coolant light-coolant_mark.jpg  

Last edited by Mazurfer; Sep 12, 2010 at 07:28 AM.
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Old Sep 8, 2010 | 08:18 PM
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so yes i have been over filling then. thanks
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