I got a 1987 Turbo II about 1.5 months go and have been constantly dealing with the low coolant buzzer and low coolant light going off intermittently. I got the car into a shop and they completely flushed all fluids, including the coolant system and bleeding it of air bubbles. This showed no results. I ordered a new sensor from Atkins and installed it, and that didn't fix it either. Today I installed a ground from the harness to the chassis, and even after that the buzzer is still going off. Any ideas? I'm basically at the point of just removing the buzzer altogether.

 

Have you checked the wire from the sensor to wherever it's terminated to, you could have a broken wire.
There is a section below this called "related posts", check there.
In one post below, replacing the sensor behind the water pump housing fixed the issue.
I am hesitant to say because I don't know where the wire terminates. Our ECU's are getting old and the capacitors in them could use a refresh.
Let's just hope the level is actually not low after refilling.

 

The wires look all good as far as I can see. I'll definitely check on the water pump sensor, I was unaware that could also set off the low coolant sensor. Heard a few things about replacing a fuse to, but I'm not sure where to start there. And yeah, even when I start the car and check that the coolant level is where its supposed to be, the buzzer goes still goes off, and since its grounded there is no way it could be going off even if it wasn't meaning the issue is probably beyond the sensor area alone.

 

To check the low coolant circuit, ground the sensor wire. The light/buzzer should go out. If it does not, you have an open in the circuit.

 

Do you mean grounding the wire coming off of the harness (not the actual sensor itself)? If so, I have done that already and it hasn't worked. Any idea where the circuit might be tripping?

 

You'll need to dig out the wiring schematic and do some troubling. There could be an open anywhere in the wire or circuit.

Get the wiring diagram here: Foxed.ca

 

Trace the brown wire back from the sensor plug. There is likely a break in it somewhere along the line...

-M

 

If the buzzer goes off with regular driving interval and or regular parked periods and if you need to add coolant with regular interval, you could have a water seal jacket leak between the block sandwiches.
You'll want to check drained oil for coolant mixture and or cappucino like foam on oil cap.

 

Thanks for the reply! There is some “slight” evidence of coolant around the coolant engine seal, but I showed the photos to Atkins rotary and they said based on the mileage of the car (39,000), and the fact there was no evidence of leakage coming out of the car, that it was likely fine. I’ll check the oil when I change it next and see how it looks. In the meantime I removed the dash and removed the buzzer so the car is drivable until I can track down the issue.

 

You may never see a leak via a coolant seal. It can get into the combustion chamber and burn off. It can be a very small leak.