Every once in while the low colant light comes on and then truns off the next time I turn of the car and stays that way for a while. Their is the normal levelof colant. Most recently it came on driving 40 mph at night while 50 degrees. Lately the car is running past the 210 degree marker. Does any one have any insight to why this may be happenning

 

210? Water pump man, my coolant light does the same thing, but the temp stays at 180 max.

 

damn, thought so, thanks

 

Bad Advice!!!!

My low coolant light comes on every once inwhile as well. I have a brand new water pump with opti swap. The sending unit for the dash gauge is located by the battery. Run your hand from the radiator cap down and you will feel it. This is what your problem is. If this is coming on you either have low coolant or a faulty unit. If you are sure your coolant is fine then simply unplug this unit. The PCM uses a separate sensor which is located on the water pump to control fans. It will not throw a code. Good Luck and before suggesting something like a water pump swap I would get all your facts straight..... As far as the temps, 210 is what temp the pcm kicks the fans on from factory. If it rising slightly higher than this I would suggest flushing the fluid. If the water pumps going then you will here it get louder and most likely will be leaking a bit from the fact that the bearings are breaking the seals on the back. Good Luck....

 

This is exactly what happened to me when my water pump lost a bearing, I don't know how you can call that bad advice... my temps were always high all the time, right now my sender unit is just messed up.

Go under the motor and check your weep hole to really see how your water pump is doing, it can be silent and on its way out, it doesn't need to make any noises before it takes a dump on you and your opti.

 

210? if you mean while not moving. thats fine for stock. low coolant sensor coming on and off while your rad is full with coolant usually is the sensor itself going bad.

 

There are so many posts on this board about this problem it is rediculous. Search them out and read them and you will find that this is a common problem with the sensor. I have the problem and I replaced the sensor and shortly after I got the same problem again. I have thoroughly checked the wiring and there are no shorts or anything like that. The best advice you can get is visually check the level and if it is OK, unplug the sensor. Don't waste your money with a new one.

 

GM did a terrible job with this sensor and havent even bothered to correct the issues since day one. The sensor is poorly designed and doesnt handle the heat that is gentereted in its location. It causes them to deteriorate. Iv replaced these sensors alot on mine and my buddies, they just keep going bad or "act up" like crazy. My p.ov. you should just unplug the sensor. If you know what your doiong you shouldnt always trust "dummy lights". Peice of mind.

 

My light only comes on when my car is sideways. Wonder why.

 

I just don't see why you would suggest something like his water pumps dying from the fact that his low coolant sensor light is coming on. I just don't see the correlation. Higher temps would not be assosciated with a dwindling water pump. Astronomical temps would be associated. 9 times out of 10 a water pump will gradual go bad by starting to leak or seize up all together. I've never really heard of one flowing less and less until it dies. Maybe it just me.

Back to the issue. I think your temps are fine. I think you should maybe put a 160 degree stat in when you flush the fluid (if you do), unplug the sensor and call it a day. I'm not really sure of the procedure/price of replacing the sensor, but I'm sure someone around here can help you with that. It really isn't an issue for me because I check/clean/flush/maintain my fluids adamatly. They named it a dummy light for a reason

 

93000 miles and my original sensor works fine. One thing to consider is how well the coolant is maintained. A gunked up system will foul the sensor. Most people neglect the cooling system.

I don't agree with your assessment that "GM did a terrible job". I agree that the sensor is a bit sensitive. However, with the coolant being of particular importance to the iron block-aluminum head engine, maybe it should be that way. Better to have the forwarning of low coolant than not. They made the others gauges as well. Are you going to unplug them, too? MHO.

 

See the correlation now?

 

I can see your point about saying am i going to unplug all my other sensors. Obviously NO. But if you go through just about every other GM vehical a LOW COOLANT warning is pointless. GM services will tell you the same. People do neglect cooling system 60 percent of repair jobs are heat releted. Hence GM uses DEX COOL now, cause to many people got lazy and didnt want to take care of it properly. If you maintain your system a LOW COOLANT DUMBY LIGHT is pointless. IF you say GM didnt do a terrible job, check the service bullitins on GM cars.

 

What ever happened to basic troubleshooting? If I'm seeing a low coolant light AND high operating temps then call me crazy but I'm going to start looking for some problem somewhere. It should be pretty simple to decide if the coolant level sensor is working or not, just LOOK and see if your radiator is full, run the car, bleed the system PROPERLY and check it again. if the level is correct then it might be pretty safe to assume the sensor isn't working correctly. Unplugging it is your decision but I've had two 4th-gen F cars and never had a bad sensor problem with either of them. Personally I think its a great idea, a sudden leak might go unnoticed until the temps suddenly skyrocket, something you might notice with a warning about low coolant level.
GM and other manufacturers spend tons of money on lots of research by people with a lot more knowledge and experience with automotive design than most of us, and the first thing someone suggests when there's a problem is all the new systems are useless and were designed by idiots and should all be disconnected, somehow I'm not sure I agree with that evaluation.
DexCool is not some magic liquid, it can deteriorate just like the green coolant, and a neglected cooling system can crud up just as easily. It's still necessary to drain, flush and properly clean your cooling system on a regular basis. Just good basic auto maintenance is all it is, these cooling systems are pretty basic.

 

Yes and those same genius's decided to put a distributor underneath a waterpump's weep hole... they also put a rear end that belongs behind a yugo in it while they had plenty of access to stronger 8.5" rear ends.

The same guys that are making decisions at GM are the same guys I had gone to school with, it doesn't matter how many degree's you have, you can't teach common sense... and yes the coolant sensor is a POS if you ask me, and its not accurate 100% of the time.

The reason I assumed a waterpump on its way out is because I have had the same damn thing happen to me, only nobody told me about it.