Dadic 78

From what I hear, these lights go off due to sensor issues. I've flushed and filled my cooling system several times in the past few years, and the light has been on ever since. My question is, does anyone know of a way to get the light to come off? (without unplugging it from the dash). Is there a replaceable sensor?

Speed Density

iTrader: (38)

Low coolant is on the radiator if my mind serves me right.

Pretty expensive sensor too.

Cross

iTrader: (10)

I have heard its optical but you can just clean it and it will be fine. Seems to be common... every 93-97 F-Body LT I have been in so far has had it on. Mine goes off and on I plan on cleaning it shortly but I have an IM to take off and redo the gaskets on as well as finishing my steering column... drive shaft swap... front rotors and brakes.... drivers side SFC.... god the list never ends.

94Firehawk161

iTrader: (7)

Is your car still running hot, like you stated in other posts?

Tsar

You can just disconnect the sensor by the radiator. That's what i did, however. first make sure that everything is OK with your car.

Flamingchicken94

iTrader: (3)

man mine is doing the same thing.

it did it last year around this same time. I added some coolant, actually a little over the mark.

but I just checked it again recently since the light came back on and it hasn't gone down a drop...

I figure it has to be the sensor.

LT1-DAN

yep, just unplug it. Just make sure you check the coolant often to make sure that it's always full. You could also take out the sensor and try to clean it, sometimes that works.

SS MPSTR

iTrader: (1)

I had the same issue a few years ago and it turned out that a new radiator cap fixed it.

Dadic 78

No, it's running great now. I replace the opti, and WP this weekend, and it's running leak free. My WP had a bad water inlet that was leaking.

The low coolant light has been coming on almost since I bought the car! It just seems to be on almost constantly now. It's just an annoyance more than anything else.

Steve in Seattle

unplug it. LS1's don't even have one.

caldercay

Some folks will tell you to unplug it. Personally, I'd rather not, since it is an
early warning device. Take it out, clean it, put it back in, fill up the radiator,
and see if it works. If the light still comes on, go get a new sensor and put it
in - having that sensor might save your engine one day.

Cross

iTrader: (10)

Ok I have heard mention of the location being the Radiator... where is it? I see the one on the water pump so where is this one?

caldercay

It's "below" the radiator cap, on the backside of the radiator. To make things
easier (I replaced mine about 2-3 weeks ago), remove the battery.

http://shbox.com/1/low_coolant.jpg

Cross

iTrader: (10)

Ahh no wonder not what I was expecting. Thanks!

Steve in Seattle

By the time you've boiled out enough coolant to trigger the sensor, you're already WAY too hot and have NO pressure in the system.

There is almost NO chance you'd trigger that low coolant light before the gauge would spike (which happens when you lose pressure and start to boil coolant from no flow).

Clean it if you want, but I wouldn't bet the farm on it actually saving anything.

caldercay

I'll have to disagree, as this just happened to me recently. I replaced the
low-coolant sensor one evening. The next day, on the way to work, the
'low coolant" light came on - I'm, like, WTH? Temp was fine. Turns out
stupid me forgot to add coolant in after replacing the sensor.

94Firehawk161

iTrader: (7)

I have found that if the cooling system has a lot of sediment or someone has mixed regular green antifreeze with Dexcool causing it to "gel", then you will usually get a "sludge" like substance collecting around the tip of the sensor. It almost looks and feels like rubber cement. To eliminate this problem on some of my cars, it took flushing the coolant system a couple of times and removing and cleaning the sensor. I wouldn't recommed unpluging the sensor, unless you are really good at checking your temp gauge while you drive! Also, make sure you have the system bled completely. If you open the radiator cap and coolant is not at the top of the neck, it is not completely bled.

hammrman31

same here.think i,ll just be safe and replace the sensor.

nuttyprofessor

Unless you have a 93 like me and they don't make the damn sensor anymore, it is fairly easy and cheap to replace ~$60 (I think).

flyinZ

iTrader: (15)

Sorry to bring up an old topic, but how do you remove the sensor from the radiator? Any help with this would be great.