I changed my water pump and cant get the low coolant light to go off. any ideas?

Question

its a 98 lumina, 3.1. i had no probs doing this pump but now the light wont go off, i opened both bleeder valves when refilling and it doesnt seem like there is any air in the system. not overheating and the thermostat works fine

never had any problems with the light before draining the coolant and the resevoir is full

pretty sure its not the sensor

Answer 1

I would really take another look at that sensor. If your sensor is in your plastic reservoir tank (only place I would know of one) then your sensor is a very simple float sensor that makes a connection when it lowers from lack of fluid. When you drained your fluid out it dropped and made its contact, now the problem is that the posts/guides that it slides up and down on are probably all gunked up from old anti-freeze fluid and the sensor is now stuck in all of that gunk where it never has been before so it has had a long time to build up goo.

You can try tapping on the side like someone else mentioned and that may work, but when I did mine, I took off the tank completely and soaked it with some cleaner and shook it all around real good to clean out all of the sludge type gunk that was in there until it was good and clean and then everything worked like it should.

You should be able to test whether its the sensor or not by unplugging the connector to the sensor, your light should go off. If it doesn't, then check your wiring for shorted wires, otherwise you'll know it's your sensor that is stuck.

Best of luck.

Answer 2

The sender is in the Coolant recovery tank. Most likely you got the radiator bled, but forgot to add more liquid to the recovery tank.

YOU DO NOT need an OBD-II scanner to turn it off! It is a simple switch, like the "washer fluid low" light. You add liquid, it goes off. The computer never gets a signal from it.

Answer 3

sender might be bad
is it the low coolant light /fill the reserve systemdrive it around the block ,check the bleaders again and fill level thease cars are prone to air pockets after reassembly
with the engine off unplug the sender if the light goes off the sender is bad test this, turn the key on ,butt ,the engine not running, plug the sender back in the light should come back on,
a scanner tool should be able to tell if the sender is good or bad if the kight stay on after you unplugged it the you plulled the wrong sender or your wiring harness has a shorted wire in it
most likely a bad sender

Answer 4

The trick is to fill it up with the radiator cap on and that includes the reservoir and when it heats up and sucks the coolant from the reservoir fill it back up and do it until it quits taking it from the reservoir
A presurised system is sometimes a pain to get it to go but with as hot as the weather has been you shouldn't have an issue.
Don

Answer 5

tap on the side of the tank. right on the sensor with the back of a screwdriver. if this does not work then replace the sensor. it is only about 20 bucks and it is easy to change. good luck.

Answer 6

Check the radiator and make sure that it is full. Then fill up the overflow reservior. The sensor is most likely located there. Filling up the reservior should fix the problem.

Answer 7

You need an OBD-II scanner to turn off your MIL (maintenance indicator lamp)